Enter your battery size, how far you're charging and your price per kWh to see what a charge costs, how long it takes with real charging losses, the range it adds, the cost per 100 km or miles, and the saving against a petrol car.
kWh
%
%
$
From your electricity bill or the charger's app
From the car's trip computer or spec sheet
Charging losses, charger power, monthly driving and petrol comparison
%
ADAC measured 5.1–7.0% at 11 or 22 kW for this kind of charger
kW
Or the car's onboard charger limit, if lower
$
To compare with a fuel car
Energy from the grid
38.3 kWh
Into the battery
36 kWh
Range added
225 km
Time at 7.4 kW
5 h 11 min
Enter your price per kWh to see what the charge costs.
36 kWh goes into the battery (20% to 80% of 60 kWh); with 6% charging losses 38.3 kWh comes from the grid.
How to use the EV charging cost calculator
Choose your currency, enter the usable battery size and the percentages you charge from and to.
Enter your price per kWh and pick the charger: a household socket, a wallbox or a fast charger.
Enter the car's efficiency in the unit your trip computer shows, and pick kilometres or miles.
Open the extra section to change the losses or charger power, and to compare a month of driving with a petrol car.
Worked example
A 60 kWh battery charged from 20% to 80% on a 7.4 kW wallbox takes 36 kWh. With 6% charging losses, 38.3 kWh comes from the grid, so at $0.30 a kWh the charge costs $11.49 and takes about 5 hours 11 minutes. At 16 kWh per 100 km it adds 225 km, $5.11 per 100 km. Driving 1,000 km a month costs $51.06 in electricity against $126 for a petrol car using 7 litres per 100 km at $1.80. In India, a 30 kWh battery charged from 10% to 100% on a household socket at ₹8 a kWh, with 18% losses, costs ₹263.41 and takes about 14 hours.
The formulas
Energy into the battery = battery size × (to % − from %)
Energy from the grid = energy into the battery ÷ (1 − losses)
Cost = energy from the grid × price per kWh; time ≈ energy from the grid ÷ charger power
Range = energy into the battery ÷ the car's consumption
Sources: ADAC charging loss tests (2023–2024, as reported by The Next Web and Vision Mobility). Everything runs in your browser.
Frequently asked questions
How do I calculate the cost to charge an electric car?
Multiply the energy you put in by your price per kWh, and add the charging losses. A 60 kWh battery charged from 20% to 80% takes 36 kWh; with 6% lost on a wallbox, 38.3 kWh comes from the grid, so at 30 cents a kWh the charge costs $11.49.
How much energy is lost when charging an EV?
It depends on the charger. In ADAC's tests of five cars, a household socket lost 12.7–24.2% of the electricity, a 4.1 kW charger 8–12.8%, and an 11 or 22 kW wallbox 5.1–7%. A fast charger lost 1–4% with a warm battery and 6–10% with a cold one. The calculator starts from the middle of these ranges; you can change it.
How long does it take to charge?
Roughly the energy drawn divided by the charger's power, or by the car's onboard charger limit if that's lower. 38.3 kWh on a 7.4 kW wallbox takes about 5 hours 11 minutes. Fast chargers slow down above about 80%, so the last part of a fast charge takes longer.
Is charging an EV cheaper than petrol?
Usually, at home rates. A car using 16 kWh per 100 km costs about $5.11 per 100 km at 30 cents a kWh with wallbox losses, against $12.60 for a petrol car using 7 litres per 100 km at $1.80 a litre. Public fast chargers cost more per kWh, so enter their price to compare.
Where do I find my car's efficiency?
In the trip computer (kWh per 100 km, Wh per km or miles per kWh) or the official figures for the model. Real-world use is usually higher in cold weather and at motorway speeds, so a figure from your own driving gives the best estimate.
Should I charge to 100%?
Many manufacturers suggest charging to around 80% for daily driving and to 100% only before long trips; check your car's manual. The calculator works for any start and end percentage.
