Calculation worksheet
EV charging time & energy
Estimate energy and charging hours from battery size, target charge, and AC power.
Enter your values and select Calculate to see a step-by-step result.
ReferenceEnergy arithmetic: hours = battery energy added ÷ (AC input kW × charging efficiency)
Planning estimate for steady AC charging. Efficiency is an editable assumption, not a guaranteed vehicle rating. Temperature, battery conditioning, taper, auxiliary loads, and power sharing can increase the time. Not a DC fast-charging curve model. Resource: https://afdc.energy.gov/fuels/electricity-stations