EV Charging Cost Calculator

Estimate what an EV charge costs

This calculator estimates the electricity cost to add a full battery-capacity amount of energy, adjusted for charger efficiency. The important distinction is battery energy versus wall energy. If the car stores 60 kWh and charging is 90% efficient, the meter may need to deliver more than 60 kWh.

Enter the battery capacity in kWh, the electricity price per kWh, and the charger efficiency. If you are not charging from empty to full, enter the energy you expect to add instead of the full pack capacity.

Formula

Wall energy = battery capacity / (efficiency percent / 100).

Charging cost = wall energy x electricity rate.

For example, a 75 kWh charge at 90% efficiency requires about 83.3 kWh from the wall. At $0.18 per kWh, the estimated cost is about $15.00.

What changes the real bill

Time-of-use pricing, demand charges, public charging session fees, cold weather, battery preconditioning, and charging losses can all move the real cost. For home charging, use the marginal electricity rate you actually pay during the charging window. For public charging, include session fees if they apply.

Compare scenarios

Run one case for home charging, one for off-peak charging, and one for a public fast charger. The same battery can have very different costs depending on rate and efficiency.