About
The site is a single-source engineering calculator library and reference site, built for the practitioner who needs the right number now — with the standard clause that justifies it. The site brings together electrical, structural, and HVAC engineering work under one roof, all grounded in the same primary documents (NEC, AISC, ASCE, IEC, NEMA, AS/NZS) that govern real installations.
What the site is
The site is a free, browser-based suite of calculators and reference pages covering the most-asked questions in practical electrical, structural, and mechanical engineering. The library currently covers thirty-three calculators (voltage drop, wire size, three-phase power, motor sizing, short circuit, fault current, transformer, generator, capacitor, inductor, RPM, truss, moment of inertia, and several more) and forty-six reference pages (NEC ampacity tables, AWG / mm² conversions, AS/NZS cable selection, AISC section properties, ASCE wind / seismic loads, NEMA motor designs, IEEE C37.2 device numbers, IEC 60364 cable selection, and more).
Every calculator returns a numerical result and shows the equation, the standard reference, and the assumptions behind it. Every reference page covers one topic in depth — definition, formulas, standards, worked example, related calculators — so a contractor or engineer can confirm in three minutes that the calculator output matches the AHJ-required clause.
Who the site is for
| Audience | Primary use |
|---|---|
| Licensed electricians | NEC-compliant conductor sizing, motor branch protection, voltage drop verification, panel calculations |
| Structural engineers | AISC section properties, beam moment of inertia, bracing design, ASCE 7 loads, truss analysis |
| Mechanical / HVAC engineers | Duct sizing, motor FLA, three-phase power, MCA / MOP for AC units, fan and pump curves |
| Contractors and builders | Wire size by amps, breaker sizing, conduit fill, AC cable selection, basic load calculations |
| Building inspectors / AHJs | Quick verification of code clauses (NEC 310.16, NEC 240.4(D), NEC 430.250, AISC F2) |
| Engineering students | FE / PE exam prep, homework cross-checking, intuition building on standard problems |
| Industrial maintenance technicians | Motor troubleshooting (FLA, RPM, power factor), cable derating, IDMT relay setting |
| Solar and EV installers | DC wire sizing, voltage drop on long runs, EV-charger circuit selection, battery sizing |
What the site covers
The library is organised in three layers. Calculators are interactive tools that take user input (voltage, current, span, load, etc.) and return a numerical answer with the formula and citations shown. Reference pages are deeper explainers — definition, formulas, code clauses, worked example, related calculators — for a single concept (Voltage, Three-Phase Power, Specific Gravity, Bracing, etc.). Standards hubs aggregate the code clauses (NEC, AISC, IEC, AS/NZS) so a user working under a specific jurisdiction can find every relevant calculator in one place.
Standards we cite
Site pages cross-reference the primary documents that govern installation and design in each jurisdiction. The four hub pages catalogue every calculator by code clause:
Other widely-cited bodies whose standards appear throughout the library: NEMA (motors, enclosures), IEEE (relays, harmonics, system protection), ASCE (wind, snow, seismic loads), ACI (concrete), AWS (welding), NFPA (fire and life safety), ASTM (materials specifications), UL (product certifications), AISI (cold-formed steel).