WireGaugeCalc Free calculator · NEC cited · works offline
Awg Calculator
Awg calculator is simple with WireGaugeCalc, since you enter your load in amps and the tool returns the matching American Wire Gauge.
The calculator reads NEC 310.16 ampacity for your material and termination column, so the gauge you get is sized to how the equipment is rated.
You skip the table lookup and go straight to the size you can pull.
Open the calculatorSmallest conductor whose ampacity meets the load, NEC Table 310.16. Field aid only, verify against the current NEC and your local authority having jurisdiction.
How this wire AWG calculator picks a gauge
Each AWG size has a fixed ampacity in the NEC tables, so the tool steps up the gauge until it meets or exceeds your load.
Copper and aluminum carry different amounts per size, so the calculator shows the gauge for each material side by side.
Ambient temperature and conductor count can lower allowable ampacity, so the result accounts for those corrections.
Inputs the calculator wire awg lookup needs
A correct AWG result depends on these factors:
- Load current in amps
- Conductor material, copper or aluminum
- Termination temperature column, often 60 or 75 degree C
- Ambient temperature for any correction factor
- Number of current-carrying conductors bundled together
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 AWG calculator account for voltage drop?
This tool sizes by ampacity first, so very long runs may still need a larger gauge to keep voltage drop under the recommended limit. Check a long run separately and confirm against the current NEC and your local authority having jurisdiction.
Why is the aluminum AWG larger than copper for the same load?
Aluminum has lower conductivity, so it carries less current per gauge and the calculator steps it up to a bigger size. Copper of the same load lands one or more gauges smaller.
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.