M·O

Validation record

What each calculator stands on, what it refuses, which outside examples it reproduces, and who has checked it. Generated from the code on every build — it cannot say something the code does not.

This build

Engine build
2026.09.09 · validated 2026-09-09
Harness
1,598 engine assertions (33 external known-answer cases) + 664 page assertions + 569 adversarial assertions over 490 page runs
Calculators
98 · 47 transcribe a published table (17 standards) · 25 carry external known-answer cases · 0 independently reviewed
What a test count shows
That the engine still answers what its author expected. It does not show that a table was transcribed correctly, that every incompatible input is refused, or that a reviewer agreed. The external cases below are the part that was NOT written alongside the engine.
Sources of external cases
eval-2026-09-07 — Public-site evaluation, report dated 7 September 2026, targeted accuracy case register (31 cases). Response: AUDIT-EXTERNAL-2026-09-09.md
niosh-94-110 — NIOSH Applications Manual for the Revised NIOSH Lifting Equation (Publication 94-110), worked examples
nws-heat — National Weather Service heat index worked example
Reviewer policy
A tool is marked independently reviewed only when a named person, with the credential shown, has checked the encoded tables and the refusal logic against the edition named. Absent that, every result is a typical approach for field use that a licensed engineer confirms.

Anchors: /validation/#<tool> — every calculator's Code basis strip links here.

Schedule Health Check (DCMA 14-point)

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/dcma.js, engine/procure.js · build 2026.09.09 · last change 2026-09-09
Scope and exclusions
The DCMA 14-point assessment, as the guide defines it. Thresholds: logic ≤ 5 %, leads 0, lags ≤ 5 %, FS ≥ 90 %, hard constraints ≤ 5 %, high float ≤ 5 %, negative float 0, high duration ≤ 5 %, invalid dates 0, missed ≤ 5 %, CPLI ≥ 0.95, BEI ≥ 0.95; resources and the critical path test are reported, not scored. Hard constraints = must start/finish on, start/finish on or before. A 15th check for dangling SS/FF logic is added as information. A pass means the network is structurally sound, not that the plan is right. We count that an assessment ran and how many checks passed — never the schedule's contents.
External known-answer cases pinned in the harness
  • SCH-01 — Synthetic three-activity XER with no baseline → Empty-population and no-baseline checks read 'not assessed', never PASS (eval-2026-09-07; engine + pages)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Voltage Drop

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/voltage-drop.js, engine/code-basis.js · build 2026.09.09 · last change 2026-09-09
Scope and exclusions
Typical approach, not engineering. Resistance method: VD = 2 · I · L · R kft ⁄ 1000 for DC and single-phase, √3 · I · L · R kft ⁄ 1000 for three-phase, where L is one-way length in feet and R kft is the conductor resistance in Ω per 1,000 ft (Chapter 9 Table 8, 75 °C, corrected for temperature per Table 8 Note 2). Written per foot instead, R = K ⁄ cmil with K = 12.9 Ω·cmil/ft copper, 21.2 aluminum, and the same drop is VD = 2 · K · I · L ⁄ cmil (√3 · K · I · L ⁄ cmil three-phase) with no ÷ 1000 — the two forms differ only by R kft = 1000 · K ⁄ cmil. The circuit multiplier (2 or √3) appears once. The impedance method uses Chapter 9 Table 9 (three single conductors in conduit, 75 °C, 60 Hz): VD = √3 · I · L · Zₑ ⁄ 1000 for three-phase, and VD = 2 · I · L · Zₑ ⁄ 1000 for DC and single-phase — the circuit multiplier replaces √3, it is not applied on top of it — with Zₑ = R cos θ + X sin θ at your power factor (Table 9 Note 2) — R and X depend on conduit material; 700, 800, and 900 kcmil are not listed, so sizing steps past them. Sizing installs the larger of the voltage-drop minimum and the Table 310.16 ampacity minimum at the chosen temperature column (240.4(D) small-conductor caps; parallel sets from 1/0 AWG per 310.10(G)) — ambient correction, conductor-count adjustment, and continuous-load factors are on the Wire Sizing calculator. The 3 % and 5 % figures are NEC Informational-Note recommendations, not requirements. A licensed engineer confirms; nothing here is a seal or stamp.
External known-answer cases pinned in the harness
  • VD-01 — 120 V, 20 A, 100 ft, 12 AWG Cu, 75 °C → 7.902 V, 6.59 % (eval-2026-09-07; pages)
  • VD-02/03 — Change the load to 40 A after a result → Result marked stale until Calculate; then 15.80 V with an overload warning (eval-2026-09-07; pages)
  • VD-05 — Maximum length at 3 %, same circuit → 45.56 ft exact; 45 ft shown (rounded down) (eval-2026-09-07; engine + pages)
  • VD-06 — Re-enter the whole-foot maximum → Within 3 % (46 ft would be 3.03 %) (eval-2026-09-07; engine + pages + 108-case invariant sweep)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Ohm's Law

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/ohms-law.js · build 2026.09.09 · last change 2026-09-09
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • OHM-01/02 — 120 V and 10 A; then a third, inconsistent 99 Ω → 12 Ω and 1,200 W; the third value is rejected (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Power

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/power.js · build 2026.09.09 · last change 2026-09-09
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Power Triangle

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/power-triangle.js · build 2026.09.09 · last change 2026-09-09
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • TRI-01 — 80 kW and 100 kVA → 60 kVAR; PF 0.8; 36.87° (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Power Factor Correction

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/pf-correction.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • PF-01 — 100 kW, PF 0.8 → 0.95 → 42.13 kvar; a 45 kvar bank gives PF 0.958 (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Conductor Size Converter

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/conversions.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Conduit Bend Total

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/bends.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Ampacity and Derating Calculator

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/ampacity.js, engine/conductors.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
Ampacity under conditions of use, not a breaker size. … … basis with ambient correction, conductor-count adjustment, termination limits, and the small-conductor caps. Conductors in cable in thermal insulation and engineering-supervision methods are not applied. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
  • AMP-01 — 6 AWG Cu, 90 °C insulation, 75 °C terminal, 40 °C ambient, 6 CCC → 75 × 0.91 × 0.8 = 54.6 A; below the 65 A termination limit (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Wire Sizing Calculator

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/wire-sizing.js, engine/ampacity.js, engine/grounding.js, engine/voltage-drop.js · build 2026.09.09 · last change 2026-09-09
Scope and exclusions
Branch-circuit and feeder conductor sizing, … basis. 210.19(A)(1) / 215.2(A)(1) continuous-load factor, … with 310.15 correction and adjustment, 110.14(C) termination limits, 240.4(D) caps, 240.4(B) next-size-up, 310.10(G) parallel minimum. Motor, welder, capacitor, and tap-rule circuits have their own articles. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
  • WIRE-01 — 100 A continuous → 125 A design; 1 AWG Cu at 130 A; 125 A device; 6 AWG Cu EGC (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Conduit Fill Calculator

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/conduit-fill.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
Fill, not pull. … …: conductor areas are the code's approximate values for round concentric-lay stranding (compact-stranded and cables differ — use the manufacturer's dimensions). Equipment grounding conductors count. Jam ratio, bends, and pulling tension are separate checks. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
  • FILL-01 — Nine 12 AWG THHN in ½ EMT → 0.1197 in² of 0.304 in² — 39.4 %, within the 40 % allowance (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Box Fill Calculator

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/box-fill.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
Volume, not wiring space. … …: conductors that originate and end inside the box (pigtails, jumpers) do not count; conductors 12 in or shorter passing through a box with no splice are counted once; a looped unbroken conductor at least twice the 300.14 minimum counts twice — enter it as two. Boxes with dimensions marked on them use the marked volume. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Cable Tray Fill Calculator

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/tray-fill.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
Fill by … …, ladder / ventilated-trough / wire-mesh tray. Cable diameters come from the manufacturer's cut sheet. Solid-bottom, channel, and ventilated-channel trays, cables over 2000 V, and Type MV/TC-ER special rules are not covered; ampacity in tray is 392.80. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Conduit Bending Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/bending.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • BEND-01 — 10 in offset at 30° → 20 in between bends; 2.679 in exact shrink (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Cable Pulling Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/pull.js, engine/conduit-fill.js, engine/conductors.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Pull Box Sizing Calculator

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/pull-box.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
Box dimensions for conductors 4 AWG and larger (… …). Raceway trade sizes drive the numbers, not conductor count; the box still needs the fittings to fit and the depth for bending. Splices, conduit bodies, and boxes with removable covers have their own provisions. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Transformer Calculator

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/transformer.js · build 2026.09.09 · last change 2026-09-09
Scope and exclusions
… … — transformers 1000 V and less. Inrush and Article 450 over 1000 V are not covered. The 240.21(C) lines below the result are the tap-rule ratio FLOORS only — an intermediate minimum, not an installable secondary conductor; the conductor is sized separately for load, termination, and the secondary device. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
  • XFMR-01 — 75 kVA, 480/208 V, three-phase → 90.2 / 208.2 A; 225 A primary and 300 A secondary maxima (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Grounding Conductor Sizing Calculator

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/grounding.js, engine/conductors.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
… Tables 250.122 and 250.66, as tables. Motor circuits (250.122(D)), parallel EGCs (250.122(F)), and the main/system bonding jumper (250.28(D), sized by 250.102(C)) are separate rules. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
  • GND-01 — 200 A device, copper EGC → 6 AWG Cu (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Cut List Optimizer

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/cutlist.js, engine/procure.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Wire Reel and Cut-Length Optimizer

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/reels.js, engine/cutlist.js, engine/procure.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Buy Quantity Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/procure.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Procurement Lead-Time Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/leadtime.js, engine/procure.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Working Space Checker (110.26)

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/clearance.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
… … for equipment likely to be worked on energized, 1000 V and below. Over 1000 V is 110.34; other spaces (equipment rooms, transformer vaults) have their own articles. Typical approach for field use; the AHJ decides. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Generator Sizing Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/generator.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Panel Load Balance Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/panel.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

NFPA 70E Boundaries and PPE Category Calculator

Standard and edition
NFPA 70E, Standard for Electrical Safety in the Workplace 2024 — The 2027 edition is published and carries substantive changes to justified energized work. These tables are the 2024 edition. Use the edition your electrical safety program has adopted.
Engine
engine/nfpa70e.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
…, the table methods only. Shock boundaries above 750 V and the DC tables are not fully encoded — read them from the standard. The PPE category method is one of two permitted methods; the incident-energy analysis (engineer's arc-flash study) governs wherever it exists. Neither replaces the electrical safety program, the risk assessment, or the qualified person. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
  • ARC-01 — 4,160 V shock boundaries → Limited approach 5 ft fixed / 10 ft movable; restricted boundary directs to the current table (eval-2026-09-07; engine)
  • ARC-02 — 240 V panel, 100 kA, 1 s → Table method refused against the 25 kA / 0.03 s parameters (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

TRIR, DART, and Severity Rate Calculator

Standard and edition
OSHA 29 CFR 1910 (general industry) current CFR — Federal text; State Plan states may be stricter.
Engine
engine/safety-stats.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • SAFE-01 — 3 DART cases, 2 recordables, 200,000 hours → Rejected — DART cases cannot exceed recordables (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Rubber Insulating Glove Class and Test Log

Standard and edition
OSHA 29 CFR 1926 (construction) current CFR — Federal text; State Plan states may be stricter.
Engine
engine/gloves.js, engine/procure.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Assured Equipment Grounding Conductor Program Log

Standard and edition
OSHA 29 CFR 1926 (construction) current CFR — Federal text; State Plan states may be stricter.
Engine
engine/aegcp.js, engine/procure.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Method of Procedure (MOP) Builder

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
page-local · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Motor Circuit Calculator (Article 430)

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/motor.js, engine/ampacity.js · build 2026.09.09 · last change 2026-09-09
Scope and exclusions
… Article 430, continuous-duty motors on the table FLC. Wound-rotor, DC, synchronous, multispeed, low-speed, and VFD-fed motors (430.122 uses the drive's input current) size differently. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
  • MOTOR-01 — 25 hp, 460 V, three-phase, 32 A nameplate, inverse-time breaker → 34 A table FLC; 42.5 A conductors; 8 AWG Cu; 90 A device; 40 A overload (eval-2026-09-07; engine)
  • MOTOR-02/03 — Three-phase with the DC motor type → Refused — no result (Table 430.247 not encoded) (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Available Fault Current Calculator

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/fault.js, engine/impedance.js, engine/conductors.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Service and Feeder Sizing Calculator

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/feeder.js, engine/ampacity.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Residential Load Calculator (NEC Article 220)

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/loadcalc.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
… Article 220, applied line by line with the section named. Floor area, nameplates, and the heating and cooling control scheme are yours to confirm; jurisdictions amend Article 220 (EVSE and garages especially), and the utility and 230.79 set service minimums. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Commercial Load Calculator (NEC Article 220)

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/loadcalc.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
… Article 220 Part III for a non-dwelling occupancy, line by line with the section named. Table 220.42(A) unit loads are minimums that already include the 125 % continuous multiplier; occupancy rows this tool has not verified against a published copy ask for the value from your code book. The optional methods for schools (220.86), new restaurants (220.88), and existing loads by demand data (220.87) are not applied here. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Multifamily Load Calculator (NEC 220.84)

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/loadcalc.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
… Article 220 for a multifamily feeder or service — Part III and the 220.84 optional method side by side. 220.84 needs one feeder per unit, electric cooking in every unit (or the 8 kW-per-unit exception, applied here), and heat or air-conditioning in every unit; house loads are Part III on top. Units are taken as identical — for a mixed building run each unit type through the Dwelling Load tool and sum by Part III. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Optional Load Calculations — Schools, New Restaurants, Existing Loads (NEC 220.86, 220.88, 220.87)

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/loadcalc.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
… Article 220 Part IV — the three optional methods that are not dwellings. Each stands in for Part III only where its section allows; the neutral is still 220.61. Typical approach for field use; a licensed engineer confirms design values. No number you enter leaves your browser — we count calculations by type only.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Harmonic K-Factor Transformer Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/kfactor.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

UPS Battery Sizing Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/ups.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Rigging Calculator — Sling Tension, CG, Crane Chart, Outrigger Pads

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/rigging.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • RIG-01 — 10,000 lb, two legs at 30° from horizontal, 9,000 lb WLL → 10,000 lb per leg; 111 % — overload flagged (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Gear Rigging Path Check

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/gearpath.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Truck Load Planner

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/truckload.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Packing List and Bill of Lading Generator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/truckload.js, engine/procure.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Schedule Comparison (XER diff)

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/xerdiff.js, engine/procure.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
What changed between two exports, nothing more. Durations in the activity's calendar days, dates from the early dates (actuals where they exist), float from total float. A change is a fact; whether it is a problem is the scheduler's call — pair it with the Schedule Health Check. We count that a comparison ran and its size — never the schedule's contents.
External known-answer cases pinned in the harness
  • DIFF-01 — Move A300 one day later → One changed activity, +1 day; nothing added or deleted (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Look-Ahead Schedule (from an XER)

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/lookahead.js, engine/procure.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
The schedule of record, sliced. In-progress activities lead week one; the rest land in the week their early start falls; 'waiting on' lists predecessors that are not complete. Level-of-effort and summary activities are excluded. Print it for the wall; the CSV goes to the crew planner. We count that a look-ahead ran and its window — never the schedule's contents.
External known-answer cases pinned in the harness
  • LOOK-01 — Three one-day activities in week one → Three tasks; two waiting; one-day durations (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Labor Histogram (from an XER)

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/histogram.js, engine/procure.js · build 2026.09.09 · last change 2026-09-05
Scope and exclusions
Units spread evenly across each assignment's window. P6 spreads on the resource calendar with curves; this is the straight-line planning view of the same numbers — close enough to see the peak and the gaps, not a substitute for P6's resource usage profile. FTE assumes 40 hours a week. Material resources are excluded. We count that a histogram ran — never the schedule's contents.
External known-answer cases pinned in the harness
  • LAB-01 — Three eight-hour assignments on a 40-hour week → 24 hours; 0.6 FTE; straight-line into week one (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Duct Bank Concrete Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/concrete.js, engine/procure.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Concrete Pads, Bases, and Excavation Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/concrete.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • CONC-01 — 120 × 120 × 6 in, 10 % waste → 1.852 yd³ in place; 2.04 yd³ ordered (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Duct Sizer (Equal Friction) and Air Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/hvac.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Pipe Pressure Loss, Velocity, Slope, and Volume Calculator

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/plumbing.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Framing Calculator — Stud Walls, Rafters, Stairs

Standard and edition
International Residential Code 2021 — Stair and framing limits vary with local amendments; header sizing is structural design and is not encoded.
Engine
engine/framing.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Structural Steel Weight Takeoff

Standard and edition
AISC Steel Construction Manual shape designations 15th ed. — Nominal weights for takeoff. HSS design wall thickness is 0.93 of nominal.
Engine
engine/steel.js, engine/procure.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Masonry Takeoff — Brick, Block, Mortar, Grout, Rebar

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/masonry.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Fire Sprinkler Hydraulics — Demand, K-Factor, Friction, Layout

Standard and edition
NFPA 13, Installation of Sprinkler Systems — Density, coverage, and hose allowance are typed in from the edition in force on your job — they are not encoded. This is a first-look demand check, not a looped-grid hydraulic submittal.
Engine
engine/fire.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Jobsite Calculator — Feet, Inches, Fractions, Triangles, Circles, Running Tape

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/dimensions.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Unit and Fastener Converter — Length, Pressure, Torque, Power, Inch ↔ Metric Bolts

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/units.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • CONV-01/02 — Blank value; then 1 in → mm → Blank is refused; 1 in = 25.4 mm (eval-2026-09-07; pages)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

AC to DC Converter — RMS, Peak, Rectifier Output, Inverter Battery Current

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/acdc.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Torque Values and Verification Log — NEC Annex I (UL 486A-B) Tables I.2 and I.3

Standard and edition
NEC Annex I (UL 486A-B / 486E) torque tables NEC 2023 Annex I — Used only where the equipment manufacturer gives no torque value. A marked or listed instruction always wins.
Engine
engine/torque.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Insulation Resistance (Megger) Test Log — Temperature Correction, PI, DAR

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/insulation.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Panel Circuit Directory and Label Generator — NEC 408.4(A)

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/directory.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

EV Charger Circuit Calculator — NEC 625 Breaker, Wire, EGC, Service Load

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/ev.js, engine/ampacity.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • EV-01 — 48 A, 240 V → 60 A circuit; 6 AWG Cu; 10 AWG Cu EGC; 11.52 kW (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

PV String Sizing Calculator — NEC 690.7 Maximum Voltage, 690.8 Currents, 690.9 OCPD

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/pv.js, engine/ampacity.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

HVAC MCA and MOCP Calculator — NEC 440 Motor-Compressor Circuits

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/hvaccircuit.js, engine/ampacity.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Transformer Inrush Calculator — Will the Primary Breaker Hold on Energization?

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/inrush.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Extension Cord and Flexible Cord Size Calculator — NEC Table 400.5(A)(1) Ampacity and Voltage Drop

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/cords.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Fiber Optic Link Loss Budget Calculator — TIA-568 Attenuation, Connectors, Splices

Standard and edition
TIA-568 optical fibre performance current — Generic cable and connector values — the reel sheet and the transceiver datasheet govern.
Engine
engine/lowvoltage.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

PoE Power Budget Calculator — IEEE 802.3af/at/bt Classes per Switch

Standard and edition
IEEE 802.3af / at / bt Power over Ethernet current — PSE allocation by class; a certification tester is the record.
Engine
engine/lowvoltage.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Noise Dose and TWA Calculator — OSHA 1910.95 and NIOSH REL

Standard and edition
OSHA 29 CFR 1910 (general industry) current CFR — Federal text; State Plan states may be stricter.
Engine
engine/safety.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Fall Clearance Calculator — Lanyard or SRL, ANSI Z359 / OSHA 1926.502

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/safety.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Heat Index and WBGT Calculator — NWS Heat Index Categories, Wet-Bulb Globe Temperature

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/safety.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • HEAT-01 — 96 °F, 65 % RH → Heat index 121 °F (eval-2026-09-07; engine)
  • NWS heat index — NWS published example → Matches the NWS table (nws-heat; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Concrete Formwork Lateral Pressure Calculator — ACI 347R Walls and Columns

Standard and edition
ACI 347R, Guide to Formwork for Concrete 2014 — SCC, admixtures, bottom pumping, and full-hydrostatic conditions fall outside the pressure formulas — check them before you set forms.
Engine
engine/civil2.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Thrust Block Calculator — Pipe Bends, Tees, and Dead Ends

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/civil2.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Rebar Takeoff Calculator — Bar Count, Laps, Sticks, and Tonnage for Slabs and Walls

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/civil2.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

NIOSH Lifting Equation Calculator — Recommended Weight Limit and Lifting Index

Standard and edition
NIOSH Revised Lifting Equation (Applications Manual) 1994
Engine
engine/lifting.js · build 2026.09.09 · last change 2026-09-09
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • LIFT-01 — 51 lb at the equation's ideal geometry, low frequency, good coupling → RWL 51 lb; LI 1.0; no 'largest penalty' named (eval-2026-09-07; engine)
  • NIOSH Ex. 1 — Manual Example 1 (destination governs) → LI ≈ 3.0 (niosh-94-110; engine)
  • NIOSH Ex. 3 — Manual Example 3 → RWL 18.9 lb (niosh-94-110; engine)
  • NIOSH Ex. 6 — Manual Example 6 → RWL 16.4 lb (niosh-94-110; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Data Center Power and Cooling Calculator — IT kW to UPS, Feeders, Tons, CFM, GPM, PUE

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/dcpower.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • DC-01 — 1,000 kW IT, PUE 1.3, UPS 96 %, 200 kW cooling units, N+1 → 1,300 kW facility; 1,041.7 kW UPS input; seven cooling units (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

VFD Circuit Calculator — NEC 430.122 Drive Input Conductors, Motor Conductors, Device, EGC

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/dcpower.js, engine/ampacity.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Motor Formulas Calculator — Synchronous Speed, Slip, Torque, Horsepower, Current, NEMA Frame

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/dcpower.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Lighting Calculator — Lumen Method Fixture Count, Watts per Square Foot, Circuits

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/dcpower.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

NEMA Plug and Receptacle Chart — Straight-Blade and Locking Configurations by Voltage and Amps

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/reference.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

NEMA Enclosure Type Selector and IP Rating Decoder — NEMA 250 and IEC 60529

Standard and edition
NEMA 250 enclosure types / IEC 60529 IP current — The NEMA-to-IP cross-reference runs one way only: a NEMA type can be said to meet or exceed an IP rating, but an IP rating cannot be converted back into a NEMA type.
Engine
engine/reference.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Wire Color Code Reference — NEC, IEC, UK, Canada, Australia

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/reference.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Communications Cable Conduit Fill Calculator — TIA-569 Fill for Cat 6A, Fiber, and Coax

Standard and edition
TIA-569 pathways and spaces current — Design-standard guidance for communications cable fill. It is not an NEC raceway requirement — do not confuse the two.
Engine
engine/fieldextras.js, engine/conduit-fill.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Fan Laws, Grille Sizing, and Hydronic Flow Calculator — Affinity Laws, Face Velocity, GPM from ΔT

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/fieldextras.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
  • FAN-01 — 1,000 → 2,000 rpm; 10,000 CFM; 1.5 in SP; 10 BHP → 20,000 CFM; 6 in SP; 80 BHP (eval-2026-09-07; engine)
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Trench Excavation Calculator — OSHA Sloping, Cut, Spoil, Trucks, Bedding, Backfill

Standard and edition
OSHA 29 CFR 1926 (construction) current CFR — Federal text; State Plan states may be stricter.
Engine
engine/fieldextras.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Busway Load and Voltage Drop Calculator — Plug-In Taps, Manufacturer Impedance, NEC 368

Standard and edition
NFPA 70, National Electrical Code 2023 — The 2026 NEC moved branch-circuit, feeder, and service load calculations out of Article 220 into the new Article 120, and changed values along the way (dwelling general lighting is 2 VA/ft², and the 125 % continuous multiplier came out of the load calculation itself). These engines are transcribed from the 2023 edition. The edition your AHJ has adopted governs — check it before you rely on a section number.
Engine
engine/lhf.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Battery Bank Calculator — Ah from Loads, Days of Autonomy, DoD, Series / Parallel, Recharge Time

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/lhf.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Rack-U Planner — Space, Weight, Power, and PDU Outlets with A/B Redundancy

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/lhf.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Electrical Formula Sheet — Ohm's Law, AC Power, Voltage Drop, Motors, Transformers, Reactance, Conversions

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/formulas.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Earthwork Calculator — Grid Cut and Fill, Stockpile Volume, Aggregate Tonnage, Grade and Slope

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/lhf.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Glycol Fill Calculator — System Volume from Pipe Segments and Equipment, Glycol and Water Gallons, Freeze Point

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/lhf.js, engine/plumbing.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Psychrometric Calculator — Dew Point, Wet Bulb, Humidity Ratio, Enthalpy, Coil Load

Standard and edition
ASHRAE Handbook — Fundamentals psychrometrics 2021
Engine
engine/lhf.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Scaffold Load Calculator — OSHA 1926.451 Duty Ratings, Plank Spans, Leg Loads at 4:1, Tie-Off Height

Standard and edition
OSHA 29 CFR 1926 (construction) current CFR — Federal text; State Plan states may be stricter.
Engine
engine/lhf.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Crane Wind Load Calculator — Sail Area, Wind Force, Percent of Chart, Stop-Work Wind

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/lhf.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Hydrant Flow Test Calculator — NFPA 291 Pitot Flow and Supply Curve at 20 psi

Standard and edition
NFPA 291, Fire Flow Testing and Marking of Hydrants 2022 — Nozzle coefficient and test quality are yours to judge.
Engine
engine/lhf.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Hip and Valley Rafter Calculator — Lengths per Foot of Run, Jack Rafter Differences, Floor Joist Takeoff

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/lhf.js, engine/dimensions.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Metal Deck and Grating Takeoff and Weld Consumable Calculator — Sheets, Weight, Electrode Pounds

Standard and edition
No published table is transcribed — arithmetic, geometry, or a reference the page names inline
Engine
engine/lhf.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.

Masonry Veneer Tie, Flashing, and Weep Calculator — TMS 402 / IBC Spacings

Standard and edition
TMS 402 / IBC masonry veneer anchorage 2022 / IBC 2021 — Maximum spacings for takeoff, not a structural design.
Engine
engine/lhf.js · build 2026.09.09 · last change 2026-09-06
Scope and exclusions
See the note on the tool page.
External known-answer cases pinned in the harness
None yet — covered by the author-written harness only (self-consistency, not independent confirmation).
Review
Author-reviewed and harness-tested. Independent reviewer: not yet assigned. Until one is, treat the result as a typical approach that a licensed engineer confirms.