WireGaugeCalc Free calculator · NEC cited · works offline
1 0 Copper Ampacity
1 0 copper ampacity is fast with WireGaugeCalc, since the app reads NEC 310.16 for the size you pick.
You set the termination temperature column, so the rated amps for 1/0 copper appear right away.
That means you confirm the conductor carries its load before you pull it.
Open the calculatorAllowable ampacity from NEC Table 310.16 at the chosen termination temperature. Field aid only, verify against the current NEC and your local authority having jurisdiction.
How WireGaugeCalc Reads 1/0 Copper Across Temperature Columns
Ampacity shifts with the column, so 1/0 copper reads different amps at 60C, 75C, and 90C.
The app holds you to the column your terminals are rated for, since terminal rating sets the usable value.
Compare it to 2 0 ampacity in the same column, as stepping up one size raises the rating.
What Sets the 1/0 Copper Rating
A few inputs decide the rated amps for 1/0 copper:
- Termination temperature column, 60C, 75C, or 90C
- Insulation type, such as THHN or XHHW
- Number of current-carrying conductors
- Ambient temperature at the run
- Any required derating factor
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
What is the ampacity of 1/0 copper at 75C?
1/0 copper is rated 150 amps in the 75C column of NEC 310.16. Check the value against the current NEC and your local authority having jurisdiction before sizing the circuit.
How does 1/0 compare to 2/0 ampacity?
2/0 copper reads higher than 1/0 in the same column, near 175 amps at 75C against 150 amps for 1/0. Stepping up one size adds current capacity when a run needs it.
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.