Heavy-duty wire for 40-50 amp circuits: electric ranges, Level 2 EV chargers, and central AC systems.
| Wire Gauge | 8 AWG |
| Diameter (inches) | 0.1285 in |
| Diameter (mm) | 3.264 mm |
| Cross-sectional Area | 8.37 mm² (16,510 circular mils) |
| Copper Resistance | 2.061 Ω/1000ft (6.76 Ω/km) @ 20°C |
| Copper Ampacity (60°C) | 40A |
| Copper Ampacity (75°C) | 50A |
| Copper Ampacity (90°C) | 55A |
| Max Circuit Breaker | 40-50A (depending on installation) |
Most 40A EV chargers (32A continuous) use 8 AWG wire. Popular for Tesla Wall Connector and ChargePoint Home.
Smaller electric ranges and cooktops on 40A circuits. Larger ranges typically need 6 AWG on 50A circuits.
3-5 ton central air conditioning systems often require 40-50A circuits.
240V hot tubs and spas typically require 40-50A circuits with 8 AWG wire.
Small sub-panels (40-50A) for garages, workshops, or additions.
Pool pumps and heaters requiring 40A circuits.
8 AWG is the most common wire size for Level 2 home EV chargers. Here's what you need to know:
Use our 240V calculator to verify voltage drop for your EV charger run.
240V Calculator