WireGaugeCalc Free calculator · NEC cited · works offline
Maximum Amperage For 14 Gauge Wire
maximum amperage for 14 gauge wire is simple with WireGaugeCalc, since the app reads the NEC 310.16 ampacity for that conductor.
You choose copper and the termination temperature column, and it returns the rated amps along with the protective breaker size.
That confirms a #14 run is protected at the right value.
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.
Ampacity And Breaker Limit For #14 Copper
The ampacity for #14 copper reads 15 amps at 60C, 20 amps at 75C, and 25 amps at 90C in NEC 310.16.
The small conductor overcurrent rule caps a #14 circuit at a 15 amp breaker regardless of the higher column values.
Since the breaker limit governs, WireGaugeCalc shows the 15 amp protection alongside the table ampacity.
What Sets The 14 Gauge Amp Limit
To find the limit for a #14 conductor, the app checks:
- Conductor material, with copper as the standard for #14 branch wire
- Termination temperature column from NEC 310.16
- The 15 amp overcurrent cap for #14 copper
- Ambient temperature and conductor count derating
- The final amps the #14 wire can safely carry
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
Can I put 14 gauge wire on a 20 amp breaker?
No, #14 copper is limited to a 15 amp breaker by the small conductor overcurrent rule. Confirm the limit against the current NEC and your local authority having jurisdiction before wiring.
Why is the 90C value 25 amps if the breaker is 15?
The 25 amp figure is for derating calculations only. The #14 overcurrent cap of 15 amps still sets the breaker and the usable load.
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.