Wire Gauge for Amperage Calculator
NEC ampacity: typical residential AWG sizes for current load.
Result
Minimum AWG
12 AWG
Rated for 20A at 60°C copper.
- Load20 A
- Recommended gauge12 AWG
- Gauge ampacity20 A
- Typical use20A circuits — outlets, kitchen
Step-by-step
- Pick smallest AWG with ampacity ≥ 20 A → 12 AWG (rated 20 A).
How to use this calculator
- Enter continuous load in amps.
- Read minimum gauge from NEC table.
About this calculator
NEC table 310.16 ampacities for typical 60°C copper conductors in residential applications. Common pairings: 14 AWG/15A, 12 AWG/20A, 10 AWG/30A. Always derate for long runs (voltage drop), bundling, and high ambient temperatures.
Frequently asked
AWG number is inversely proportional to diameter. 14 AWG is thinner than 12 AWG.
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