EV Charging Cost Calculator

What it costs to charge an EV

Charging an electric vehicle at home is usually far cheaper than filling a gas tank — but how much exactly? This calculator works out the cost and the energy used to bring your battery from one state of charge to another at your electricity price.

Why efficiency matters

Not all the electricity you pull from the wall lands in the battery — some is lost as heat in the charger and cabling. At 90% efficiency you draw about 11% more energy than the battery gains, and you pay for every kilowatt-hour that leaves the grid, so the tool bills the grid-side figure.

FAQ

Why charge only to 80%?

For everyday use, many manufacturers recommend charging lithium batteries to 80% to extend their lifespan, reserving 100% for long trips. That's why the default range is 20–80%.

Is this EV charging calculator free and private?

Yes. It's free with no sign-up, and everything is calculated in your browser, so your battery size, electricity rate, and charge levels are never sent anywhere or stored.

What charging efficiency should I enter?

Home AC charging is typically around 85–90% efficient, while DC fast charging can be a little higher. If you're unsure, 90% is a reasonable default — it accounts for energy lost as heat in the charger and cables, which you still pay for at the meter.

Does this estimate the cost of public DC fast charging?

It can, as long as you enter the per-kWh price the network charges. Note that public fast chargers are usually billed at a higher rate than home electricity, and some also add session or time-based fees that this calculator doesn't include.

Why is the energy I pay for more than my battery's capacity gained?

Because charging isn't perfectly efficient. To add a given number of kilowatt-hours to the battery, you have to pull more from the grid — the difference is lost as heat. The calculator bills the larger grid-side figure, which is what actually appears on your electricity bill.

Does it work on mobile?

Yes. The calculator is fully responsive and runs in any phone or tablet browser, so you can check charging costs on the go without installing an app.