EV home charging cost calculator
Estimate a charging session using battery energy or a wall-meter reading, with clearly defined charging losses.
Your charging session
Example inputsResults update as you type. All costs are in U.S. dollars. See result ↓
Grid kWh = battery kWh ÷ (1 − loss fraction).
For your own rate, add per-kWh supply and delivery charges; leave out fixed fees. Find it on your bill →
Example result — edit inputs to match your use
Estimated charging cost55.56 kWh drawn from the wall
50 kWh ÷ (1 − 10%) × $0.1831 = $10.17Excludes charger installation, parking, subscription fees and separately billed charges.
↑ Edit inputsBattery energy and billed energy are different.
Your utility bills for electricity drawn from the grid. Some of that energy is lost in conversion and battery charging. If you want 50 kWh added to the battery with an assumed 10% of wall energy lost, the modeled grid draw is 50 ÷ 0.90 = 55.56 kWh.
At an example 20¢/kWh, that is $11.11. Multiplying battery energy by 1.10 would use a different definition of loss and understate this estimate.
If you have a wall-meter reading
Select “Energy drawn from the wall.” The cost is simply wall kWh × rate. Changing loss in this mode only estimates how much energy reaches the battery; it does not add a second loss charge.
Why start at 10%?
10% is an illustrative assumption, consistent with an example in the DOE/EPA energy-flow explanation. It is not a measured value for your car. Charging level, temperature, battery conditioning, and state of charge affect actual losses.
Does overnight charging save money?
Only if your applicable electricity price is lower then. The result’s 20% lower-rate scenario is hypothetical. Enter the actual off-peak rate to compare. If charging crosses rate periods, calculate each period separately and add the costs.