A breaker protects the wire, so breaker and wire size go together. This chart pairs common household circuits with their typical breaker and copper wire size.
| Circuit | Breaker | Copper wire |
|---|---|---|
| General lighting | 15 A | 14 AWG |
| Kitchen and bath outlets | 20 A | 12 AWG |
| Microwave, disposal | 20 A | 12 AWG |
| Electric dryer | 30 A | 10 AWG |
| Water heater | 30 A | 10 AWG |
| Electric range | 40 – 50 A | 8 – 6 AWG |
| EV charger (Level 2) | 40 – 60 A | 8 – 6 AWG |
Match breaker to wire. Never put a breaker larger than the wire is rated for. For continuous loads, size the circuit to 125% of the load (the 80% rule).
See the Wire Ampacity Chart and What Wire Size Do I Need.