EV charging time calculator
Work out how long an electric car takes to charge, from the battery size and the charging power.
Uses only the numbers you enter. Time is energy added divided by charging power.
Result
Charging a 60 kWh battery from 20% to 80% at 7 kW takes about 5 hours 9 minutes.
5 hours 9 minutes
at full charging power
| Energy added | 36 kWh |
|---|
Rapid charging slows down as the battery fills, so the last part takes longer than this.
Show the workings
| Step | Sum | Answer |
|---|---|---|
| Energy to add | 60 kWh × (80% − 20%) | 36 kWh |
| Time at full power | 36 kWh ÷ 7 kW | 5.143 hours |
What this leaves out or assumes
- Assumes the car takes the charger's full power the whole time. Rapid chargers slow down as the battery fills, usually above about 80%, so charging to 100% takes longer than this.
- A little energy is lost as heat while charging, so a charge takes slightly longer and costs slightly more than this.
- The car's own onboard charger can limit the power. A home charger can only deliver what the car accepts.
Where the figures come from
This sum uses only the numbers you entered.
Time to add 80% of a battery
| Battery | 3 kW | 7 kW | 11 kW | 22 kW | 50 kW |
|---|---|---|---|---|---|
| 40 kWh | 10h 40m | 4h 34m | 2h 55m | 1h 27m | 0h 38m |
| 60 kWh | 16h 00m | 6h 51m | 4h 22m | 2h 11m | 0h 58m |
| 80 kWh | 21h 20m | 9h 09m | 5h 49m | 2h 55m | 1h 17m |
What sets the charging speed
The power is the lower of what the charger gives and what the car can take. A car that takes 7 kW charges no faster on a 22 kW charger. A charger's power is current times voltage: at the declared UK mains voltage of 230 volts, every 10 amps is 2.3 kW.
Rapid chargers slow down as the battery fills, to protect it, so the last part of a charge takes longer than this sum. A little energy is also lost as heat. The EV charging cost calculator works out what a charge costs.