Advanced options
*Most EVs charge AC at 7-11 kW regardless of the charger's rating: 22 kW AC needs a rare 3-phase onboard charger. DC rapid speeds taper sharply above 80%, which is why public rapid stops target 80%, and cold batteries charge slower. Times shown assume the car can accept the charger's full power.
What The EV Charge Time Calculator Works Out
- Charge time: energy divided by power. Taking a 60 kWh battery from 10% to 80% adds 42 kWh: six hours on a 7 kW home wallbox, 18-plus hours on a 2.3 kW three-pin "granny" cable, around 50 minutes on a 50 kW rapid and under 20 minutes at 150 kW if the car can take it.
- Home charging cost: the energy added multiplied by the standard home rate (defaulting to the current Ofgem price cap unit rate), with the same charge on a typical 7p overnight EV tariff underneath. The 42 kWh example is about GBP 11 at the standard rate and under GBP 3 off-peak, which undercuts petrol several times over.
- Car's maximum charging power (advanced): AC charging is capped by the car's onboard charger, 7 kW to 11 kW for most models, so a 22 kW post is no faster for them; DC rapid charging bypasses it but has its own ceiling (50 kW to 250 kW depending on the car). Enter your car's figure and the time uses the lower of car and charger.
- Charging losses (advanced): roughly 10% of the electricity drawn becomes heat in the onboard charger and cables, more on a three-pin plug and in cold weather. Losses lengthen the charge and raise the bill: the "energy drawn from the socket" card shows what the meter actually records.
- Rapid-charging taper (advanced): DC charging slows sharply above about 80% to protect the cells, the last 20% often taking as long as the previous 40%. Select this and the time above 80% on a DC charger is calculated at half power, which is why rapid-stop strategy is arrive low and leave at 80.
- Electricity rates (advanced): override the standard rate (the current Ofgem price cap by default) and the 7p off-peak default with your own tariff. Dedicated EV tariffs usually give a 4 to 6 hour overnight window; the "cost on the off-peak tariff" card shows the saving per charge.
- Range added (advanced): energy added multiplied by the car's efficiency, typically 3 to 4 miles per kWh, with the miles gained per hour plugged in alongside. A 7 kW wallbox adds roughly 25 miles an hour; a three-pin plug about 8.
- Ready at (advanced): enter the time you plug in and the card shows when the charge finishes, so you can check it fits inside an off-peak window or is done before the morning.
- Full 0 to 100% (advanced): the time for a complete charge on the same charger, with the taper if selected. For daily use most owners charge to 80% and reserve 100% for long trips; cold batteries accept less power until warmed, and preconditioning en route to a rapid charger restores the advertised speeds.