EV Charging Cost Calculator — Home & Public
An EV charging cost calculator works out what you pay to run an electric car. Enter your monthly miles, your car's efficiency and your electricity rates, and it shows your monthly charging bill, cost per mile and the cost of a full charge — plus how it compares with a petrol car.
How it works
- Enter how many miles you drive each month and your car's efficiency in miles per kWh.
- Enter your home electricity rate and your public charging rate, and how much of your charging happens at home.
- See your monthly cost, cost per mile, the cost of a full charge and the saving against a petrol car.
Formula
Worked example
Drive 1,000 miles a month at 3.5 miles per kWh, charging 90% at home at $0.17 per kWh and 10% in public at $0.45, with 10% charging loss. The car needs 317.46 kWh from the wall, at a blended $0.198 per kWh — $62.86 a month, or about 6.3 cents a mile. The same miles in a 30 mpg petrol car at $3.50 a gallon cost $116.67, so the EV saves about $53.81 a month.
Frequently asked questions
How much does it cost to charge an EV per month?
For most drivers it is $40 to $80 a month at home. At 1,000 miles a month, 3.5 miles per kWh and a home rate of $0.17, it is about $62.86 a month including charging losses. Enter your own numbers above for your exact figure.
How do I calculate EV charging cost?
Divide your monthly miles by your car's efficiency (miles per kWh) to get the energy in the battery, divide by (1 − charging loss) to get the energy from the wall, then multiply by your price per kWh.
What is the cost of a full charge at home?
Multiply your battery size by your home rate, allowing about 10% for charging loss. A 75 kWh battery at $0.17 per kWh costs about $14.17 for a full charge from empty.
Is charging an EV cheaper than petrol?
Usually yes. In the worked example above, 1,000 miles costs $62.86 in electricity against $116.67 in petrol for a 30 mpg car. The gap is biggest when you charge at home overnight and smallest on expensive public fast chargers.
What is charging loss?
Some energy is lost as heat while charging, so the meter records more than the battery stores. About 10% is typical for home Level 2 charging. The calculator includes it in the wall energy.
How much does public fast charging cost?
Public DC fast charging usually costs $0.40 to $0.60 per kWh, roughly two to three times a home rate. That is why the calculator asks what share of your charging happens in public.