EV Charging Cost Calculator
Estimate how much an electric car charge will cost, how many miles it adds and the real cost per mile using your battery size, tariff and charging loss.
Calculate your EV charge cost
Enter your battery size, starting charge, target charge and electricity price. The calculator estimates the energy added, charging loss, miles added and total cost.
How the EV charging cost is calculated
The calculator works out how much energy you need to add to the battery, adjusts for charging loss, then multiplies the energy from the wall by your electricity price.
Energy added = battery size × (target charge - current charge) ÷ 100
Energy from wall = energy added ÷ (1 - charging loss %)
Charge cost = energy from wall × electricity price per kWh
Miles added = energy added × miles per kWhFor example, charging a 60kWh battery from 20% to 80% adds 36kWh to the battery. With a 10% charging loss, the charger needs about 40kWh from the wall.
Assumptions to check before relying on the result
The default electricity price is only a starting point. Your actual cost could be much lower on an off-peak EV tariff, or much higher on a motorway rapid charger.
- Battery size: Some manufacturers quote gross capacity, while usable capacity can be lower.
- Charging loss: Home AC charging often has losses, and very cold weather can make charging less efficient.
- Efficiency: Your kWh usage per mile changes with speed, temperature, tyres, route and driving style.
- Tariff: An EV tariff may offer cheaper overnight charging than a standard household electricity rate.
Home charging vs public charging
Home charging is usually the cheapest way to charge an EV, especially if you use a time-of-use tariff. Public rapid charging can be convenient, but it can change the cost per mile dramatically.
| Charging type | Typical use | Cost behaviour |
|---|---|---|
| Home overnight | Regular commuting and planned charging | Often lowest cost, especially on EV tariffs |
| Home standard rate | Everyday charging without a specialist tariff | Usually predictable and cheaper than rapid charging |
| Public rapid | Long journeys and top-ups away from home | Usually higher cost per kWh |
Why cost per mile matters
Cost per mile makes EV charging easier to compare with petrol and diesel. Once you know your pence-per-mile figure, you can compare a journey in this calculator against the Fuel Cost Calculator or estimate regular travel in the Commute Cost Calculator.
A cheap home charge can make an EV very inexpensive per mile, but frequent public rapid charging can narrow the gap versus petrol or diesel.
EV charging cost FAQs
How much does it cost to charge an electric car?
It depends on the battery size, how much charge you add and your electricity price. A partial top-up is often more useful to calculate than a full 0% to 100% charge.
Should I include charging loss?
Yes. Charging loss means the energy drawn from the wall is higher than the energy that reaches the battery. A 10% assumption is a practical starting point, but the real figure can vary.
Is EV charging cheaper than petrol?
Often, but not always. Home charging can be much cheaper per mile than petrol, while expensive rapid charging can reduce the saving. Use this calculator with the MPG Calculator to compare both sides.