WireGaugeCalc Free calculator · NEC cited · works offline
Electrician Calculator App
Electrician calculator app is quick with WireGaugeCalc, since the tool runs the daily NEC math right on this page.
The calculator covers wire size, voltage drop, conduit fill, box fill, and ampacity in one place.
You skip the paper tables and get an answer you can act on at the panel.
Open the calculatorEnter any two values and read the rest.
Ohm’s law: V = I × R and P = V × I. Field aid only, verify against the current NEC and your local authority having jurisdiction.
Everyday Field Math In One Free Tool
An electrician moves between many calculations a day, so a single tool that holds them saves trips back to the truck.
WireGaugeCalc applies Ohm's law, motor full-load amps, and conduit bend math with the same NEC tables you already use.
Each result shows the inputs so you can recheck the work before you commit the run.
What The Calculator App Handles On The Job
The tool covers the common jobsite calculations:
- Wire size from load, length, and termination temperature
- Voltage drop on copper or aluminum branch circuits
- Conduit fill at the NEC Chapter 9 limits
- Box fill volume per NEC 314.16
- Ampacity by termination temperature column
One app for every NEC calculation
WireGaugeCalc keeps the calculations you reach for most in one place:
- Voltage drop and wire sizing for any run
- Conduit fill for EMT, PVC, and RMC
- Box fill and junction box sizing
- Ampacity and temperature derating
- Motor circuit and load calculations
- Conduit bend offsets and saddles
Built for the field, works offline
The whole app runs on your phone, so it keeps working in a basement, an attic, or a job site with no signal.
There is no account to create and nothing to load. Open it, run the number, and get back to work.
- No signup and no signal needed
- Answers in a tap, not a spreadsheet
- Same tool on phone, tablet, and desktop
Every result cites the NEC article
Each answer shows the table or formula it came from, so you can check the method and learn the code as you go.
That makes the app useful on the job and during exam prep, since the reasoning is right next to the number.
Switch the code year your job runs on
Jurisdictions adopt the NEC at different times, so you can match the calculation to the code in force:
- NEC 2017, 2020, and 2023 tables
- Copper and aluminum conductors
- 60, 75, and 90 degree C terminations
- Single-phase and three-phase systems
Run the number, then get back to work
Stop flipping through a paper book or hopping between calculator sites. Enter your values, read the code-cited answer, and move on. Free to use, no signup.
Open the calculatorFrequently asked questions
Does the electrician calculator app cost anything?
No, WireGaugeCalc is free to use on this page with no sign-up. You enter your values and read the result right away.
Are the results code accurate?
The tool uses the NEC tables for ampacity, fill, and box volume so the math follows the code. Always confirm a final design against the current NEC and your local authority having jurisdiction.
Is WireGaugeCalc free to use?
Yes. Every calculator is free to run with no signup. A paid tier adds saved projects, PDF reports, and extra code years, but the core math stays free.
Does it work without internet?
Yes. The app runs on your device, so it keeps working with no signal on a job site, in a basement, or in an attic.
Are the results code accurate?
Results follow published NEC tables and standard formulas, and each answer shows the article it came from. It is a field aid, not a stamp of approval, so verify against the current code and your local authority before you wire anything.
Which NEC code year does it use?
You can switch between NEC 2017, 2020, and 2023, since jurisdictions adopt the code at different times. Pick the year your job runs on.