This EV charging cost calculator shows how much it costs to charge your electric car, what you pay per 100 miles or kilometers, and your yearly charging cost. It works with any currency and includes charging losses.
How EV charging cost is calculated
Energy needed = battery size × (charge to % − charge now %)
Energy from the grid = energy needed ÷ charging efficiency
Cost = energy from the grid × electricity price per kWh
Some electricity is lost as heat while charging, so you pay for more energy than ends up in the battery. Home charging typically loses around 10%, which is why the default efficiency is 90%.
Worked example
A car with a 75 kWh battery charges from 20% to 80%, adding 45 kWh. At 90% efficiency, 50 kWh comes from the grid. At $0.17 per kWh, the charge costs $8.50. If the car travels 3.5 miles per kWh, driving 100 miles costs about $5.40, and 12,000 miles a year costs about $648.
Where to find your numbers
Your electricity price per kWh is on your utility bill; if you have a time-of-use tariff, use the overnight rate when you charge at night. Battery size is in your car’s specifications. Efficiency in miles or km per kWh is shown in most cars’ trip computers.
Frequently asked questions
Why charge to 80% instead of 100%?
Many manufacturers recommend charging to around 80% for daily use to reduce battery wear, and rapid charging slows down sharply above 80%. Check your car’s manual for its guidance.
Is public rapid charging more expensive?
Usually, yes. Public rapid chargers often charge much more per kWh than home electricity, and some add session or per-minute fees. Enter the charger’s price per kWh to compare.
Is charging an EV cheaper than buying gas or petrol?
It depends on local electricity and fuel prices and on your car’s efficiency. Compare the cost per 100 miles or km here with your current fuel cost for the same distance.