EV Charger Circuit Calculator

Size the electrical circuit for a Level 2 EV charger: breaker, wire gauge, daily energy needs, and charging costs.

Charger Amperage

Circuit Voltage

Electrical Panel Size

Daily Driving Distance

miles

EV Efficiency

mi/kWh

Tab to move between fields

Required Circuit Amps

50 A

Breaker Size50 A

Wire Gauge (AWG)6 AWG

Daily Energy Needed10 kWh

Nightly Charge Time1 hours

Monthly Charging Cost$39.00

How to Use This Calculator

Enter Charger Amps (Level 2 chargers are typically 32–50 A) and Voltage (240 V for Level 2).
Input your Existing Panel Amps to check whether a panel upgrade is required for the new circuit.
Enter Daily Miles driven so the calculator can show Daily kWh needed and Charge Time Hours.
Review Required Circuit Amps and Breaker Size to specify the correct breaker and wiring for your electrician.
Check Wire Gauge — undersized wire is a fire hazard; the calculator selects the NEC-compliant gauge.
Use Monthly Charging Cost to estimate the impact on your electricity bill at current utility rates.

How the result changes with Charger Amperage

Charger Amperage: Charger continuous draw in amps. Common: 32A (7.7kW), 40A (9.6kW), 48A (11.5kW).
Circuit Voltage: Voltage of the dedicated circuit. Standard US Level 2 is 240V.
Electrical Panel Size: Main electrical panel amperage. 200A is standard for modern homes.
Daily Driving Distance: Average miles driven per day that need to be recharged overnight.
EV Efficiency: Miles per kWh for your EV. Typical: 3-4 for sedans, 2-3 for trucks/SUVs.

Required Circuit Amps: Minimum circuit ampacity per NEC 80% continuous load rule (125% of charger amps).
Breaker Size: Nearest standard breaker size that meets the circuit requirement.
Wire Gauge (AWG): Minimum copper wire gauge per NEC Table 310.16. Lower number = thicker wire.
Daily Energy Needed: Energy required to replenish your daily driving distance.
Nightly Charge Time: Hours needed to charge your daily driving amount.
Monthly Charging Cost: Estimated monthly electricity cost for EV charging at $0.13/kWh.

Identify Input Parameters
4 parameters
Charger Amperage = 40, Circuit Voltage = 240, Electrical Panel Size = 200, Daily Driving Distance = 35 = 5 input(s) provided
Calculate Required Circuit Amps
Required Circuit Amps
50 = 50
Calculate Breaker Size
Breaker Size
50 = 50
Calculate Wire Gauge
6 = 6