EV charging time calculator
Estimate how long an electric car could take to charge at home, on AC destination charging or on a rapid DC charger. The calculator respects both the charger limit and the car’s own maximum charging rate.
Battery and charger
Why charging time is not simply battery ÷ charger power
The calculator first uses the lower of the charger output and the vehicle’s maximum rate. It then applies an average-power factor. The default is 90% for AC and automatically switches to 75% when you choose rapid DC, but you can edit it.
For example, a 77kWh battery going from 20% to 80% needs 46.2kWh added. A 7.4kW home charger with a 90% average-power factor gives about 6.7kW average, producing an estimate just under seven hours. A rapid charger can be much faster, but the correct average factor depends heavily on the actual car’s charging curve.
Use manufacturer 10–80% figures when available
If your car manufacturer publishes a tested 10–80% time for a specified charger, that figure is normally more useful than a generic calculator. This tool is best for planning unknown combinations, home charging, and understanding why the charger’s headline kW rating is not automatically the power your car receives.
How to use the EV charging time calculator
Enter the usable battery capacity, starting and target charge levels, charger power and the vehicle’s maximum charging rate. The usable charging power is limited by the lower of the charger and vehicle limits, while the average-power factor allows for real charging to be slower than the headline maximum.
Worked example
A 60 kWh battery charged from 20% to 80% needs 36 kWh. On a 7.4 kW AC charger with a 90% average-power factor, the effective rate is about 6.7 kW, giving a simple estimate of roughly 5.4 hours.
EV charging time FAQs
Why does rapid charging slow down near full?
Battery management systems normally reduce charging power as the battery fills, especially at high states of charge, to control temperature and protect the cells.
Will an 11 kW wallbox always charge at 11 kW?
No. The car’s onboard AC charger, the electrical supply and charging conditions can all impose a lower limit.
Why can cold weather increase charging time?
A cold battery may accept less power until it warms, and some incoming energy can be used for battery conditioning rather than immediately increasing state of charge.