What gauge extension cord do I need for an electric vehicle charger?

Use a cord rated for the amps, not just the volts. For Level 1 chargers (120V, 12 amps continuous), get a 12-gauge cord minimum—10-gauge if over 50 feet. For Level 2 (240V, 20-40 amps), use a 6-gauge or 8-gauge dedicated EV extension cord. Always match the cord’s rating to your charger’s max amperage.