A Canadian CompanyAutomotive Wire Amperage Chart | ||||||
The chart below shows the amount of Amps the gauge of wire can manage. The general rule of thumb is to use a size of wire that is 30% more in Amperage rating than is required. Notice as the length of the wire increases the amount of Amps safely carried by the wire drops accordingly. | ||||||
| Automotive Wire Size | 5 Amps | 10 Amps | 15 Amps | 20 Amps | 25 Amps | 30 Amps |
| 20 Gauge Wire (AWG) | 4.5 ft | 2.2 ft | 1.6 ft | |||
| 18 Gauge Wire (AWG) | 7.3 ft | 3.7 ft | 2.4 ft | 1.8 ft | ||
| 16 Gauge Wire (AWG) | 11.5 ft | 5.8 ft | 3.8 ft | 2.9 ft | 2.3 ft | 1.9 ft |
| 14 Gauge Wire (AWG) | 18.4 ft | 9.2 ft | 6.1 ft | 4.6 ft | 3.7 ft | 3.1 ft |
| 12 Gauge Wire (AWG) | 29.4 ft | 14.7 ft | 9.8 ft | 7.4 ft | 5.9 ft | 4.9 ft |
| 10 Gauge Wire (AWG) | 46.8 ft | 23.4 ft | 15.6 ft | 11.7 ft | 9.4 ft | 7.8 ft |
| 8 Gauge Wire (AWG) | 74.4 ft | 37.2 ft | 24.8 ft | 18.6 ft | 14.9 ft | 12.4 ft |