Installing a Level 2 EV charger at home requires the right wire gauge and breaker size to handle the load safely. This calculator determines the electrical requirements based on your charger's specs and wire run distance.
Charger Specs
A
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Scenario: You're installing a 40-amp EV charger with a 30-foot wire run from the panel.
Result: Breaker: 50A (125% of 40A, rounded to standard size). Wire: 8 AWG copper. Total wire needed: about 70 ft (30 ft x 2 conductors + 10 ft for routing).
The NEC requires the breaker to be 125% of the charger's continuous load. A 40A charger needs a 50A breaker. A 48A charger needs a 60A breaker. Always round up to the next standard breaker size (15, 20, 30, 40, 50, 60, 80, 100).
Use 8 AWG copper for runs up to 50 feet. For runs over 50 feet, step up to 6 AWG to prevent voltage drop. Always use copper wire, not aluminum, for EV charger circuits. Use 6/3 NM-B (Romex) or THHN in conduit.
The charger unit costs $300-$700. Electrical installation runs $500-$2,500 depending on panel capacity and wire run distance. If your panel needs an upgrade to accommodate the load, add $1,500-$4,000 for a panel upgrade.
In most jurisdictions, electrical work over 120V requires a licensed electrician and a permit. Even if you're comfortable with electrical work, get a permit -- your insurance and the charger warranty may require it. An incorrect installation is a serious fire hazard.
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