9 calculators
Each app is purpose-built for one calculation. Free with rewarded ads, $2.99 to unlock Pro (lifetime).
Box Fill
NEC Art.314Tap to open the calculator.
OpenBreaker Size
NEC Art.240Tap to open the calculator.
OpenConduit Fill
NEC Ch.9Tap to open the calculator.
OpenElectrical Load
NEC Art.220Tap to open the calculator.
OpenGrounding Size
NEC Art.250Tap to open the calculator.
OpenMotor Fla
NEC Art.430Tap to open the calculator.
OpenTransformer
NEC Art.450Tap to open the calculator.
OpenVoltage Drop
NEC 210/215Tap to open the calculator.
OpenWire Size
NEC Art.310Tap to open the calculator.
Open100% offline
No account, no signup, no internet required.
Code-compliant
Validated against NEC 2023 — current revision.
PDF export (Pro)
Generate professional reports — share via email or save.
$2.99 lifetime
One-time per app. No subscription, no recurring fees.
Built for the field, not the office
Electools is a suite of 9 focused calculators for working tradespeople. Each app does one job and does it fast — no bloated menus, no sign-in, no spinner waiting on a connection. Open it on the ladder or in the truck and get an answer in seconds.
Every result is backed by NEC 2023 and shows the exact code reference behind the math, so you can check it against the book or hand it to an inspector with confidence. Calculations run entirely on your device — your inputs never leave your phone.
Start free with rewarded ads, then unlock Pro for a one-time $2.99 per app to remove ads, save unlimited history, and export clean PDF reports. No subscriptions, ever.
Frequently asked questions
Are these calculators free?
Yes. Every app is free to use with rewarded ads. A one-time $2.99 Pro unlock removes ads, saves unlimited calculation history, and enables PDF export — there is no subscription.
Do they work without internet?
Completely. All Electools apps run 100% offline with no account required, so they work in a basement, a mechanical room, or anywhere with no signal.
Which code edition do they follow?
Calculations are validated against NEC 2023 (current revision). Each result shows the specific article or table it is based on so you can verify it.
Are they on iPhone and Android?
Yes — Electools apps are available on both the App Store and Google Play. Open any calculator above to get the download links.