🔋 EV Charging Cost Calculator

Enter your EV's battery capacity, how much you're charging, your electricity rate, and estimated range to calculate charging cost and cost per mile.

Battery Capacity (kWh)

Percent to Charge (%)

Electricity Rate ($/kWh)

Estimated Range at Full Charge (miles)

How the charge is priced

The battery is the meter. A percentage of its capacity is the energy added, and the same percentage of the rated range is the distance it buys:

kWh added     = battery kWh x percent / 100
cost          = kWh added x rate per kWh
miles added   = range x percent / 100
cost per mile = cost / miles added

Taking a 75 kWh battery up by 80% at $0.13/kWh adds 60 kWh for $7.80, worth 240 miles of the car's 300, so 3.3 cents a mile. The percentage cancels out of that last figure: cost per mile is battery x rate / range whatever size the charge is.

Which rate to type in

This is the input that decides the answer, and it is not one number. Off-peak EV tariffs run 5 to 10 cents a kWh overnight, the flat residential rate might be 13 to 20, and public DC fast charging is commonly 35 to 60 cents. Read your own off the bill or the charger's screen rather than trusting a default.

Same charge at $0.48 on a fast charger: $28.80, and 12 cents a mile.
A 30 mpg petrol car at $3.50 a gallon costs 11.7 cents a mile.

So charging at home is roughly a third of the fuel cost, while fast charging on a road trip is about the same as filling up. That difference, not the car, is where EV running costs are won or lost.

Charging is not perfectly efficient. The meter records roughly 10% more than the battery gains, so add about a tenth to the cost shown for what actually lands on your bill.

Frequently asked questions

How much does it cost to charge an electric car at home?

Adding 60 kWh to a 75 kWh battery at 13 cents a unit costs $7.80 and covers about 240 miles. On an overnight tariff at 8 cents the same charge is $4.80.

Is charging an EV cheaper than buying petrol?

At home, comfortably: 3.3 cents a mile against 11.7 for a 30 mpg car at $3.50 a gallon. At public fast-charger prices the two are close to level.

Why did the charger bill me for more kWh than my battery took?

Conversion and thermal losses in the onboard charger and the pack. Around 10% of what goes through the plug never reaches the cells, and it is higher in cold weather when the battery is being warmed.