Put a price on your next mile

EV charging cost calculator

Compare standard home, off-peak and public charging for the same mileage. Include charging losses and choose the mix that reflects how you actually drive.

No email requiredYour numbers, visible assumptionsResults stay in your browser

Make it your scenario

The starting values are examples. Replace them with your bills or installation proposal.

Annual mileage · miles

Your expected driving, including trips that need a public charge.

Driving efficiency · miles/kWh

Use the car’s driving efficiency, before charging losses. Weather and speed change this figure.

Charging efficiency · %

90% means 10% of purchased energy is lost. An example assumption, not a measured figure for your car.

Charging energy bought at home · %

The remainder is bought at the public rate below.

Home charging bought off-peak · %

A share of home charging, not all driving. Allow for short windows, shared loads and tariff eligibility.

Standard home rate · p/kWh

Example only. Check the normal rate on your proposed tariff.

Off-peak home rate · p/kWh

Example only. Check the available window and compatible vehicle or charger.

Public charging rate · p/kWh

Use a realistic average of the public chargers you expect to use.

Put the result in context

Charging costs, tariff trade-offs and your installation brief

Read the guide ↗

A result is a starting point

Understand what
changes the answer.

Why does the meter supply more energy than the car uses?

Energy is lost between the electricity supply and the battery. At 90% charging efficiency, adding 9 kWh requires 10 kWh from the supply. If your efficiency figure already measures electricity at the wall per mile, do not add losses twice: set charging efficiency to 100%.

Will an EV tariff save me money overall?

Compare the whole household bill. A cheap car-charging window can come with a different daytime rate, standing charge or eligibility conditions. First check how much charging actually fits into the window. Then account for the electricity used by the rest of the home. These results isolate vehicle energy costs so you can see that part clearly.

Does a 7 kW charger always supply 7 kW?

No. The vehicle’s AC charging limit, available supply and load-management settings can restrict power. The calculator does not promise a charging time. Ask an installer to check the car, parking position, cable route, electrical supply and any simultaneous battery or heat-pump demand.

The working, made visible

How this tool works

Driving energy = annual miles ÷ miles per kWh. Purchased energy = driving energy ÷ charging efficiency. Split it between home and public charging, then split home energy between standard and off-peak rates. Add the three costs. Comparison bars price the same purchased energy entirely at each rate.

What to allow for

All rates are editable examples including VAT, not live supplier offers. One charging-efficiency assumption applies to every route. The tool excludes charger installation, parking, subscriptions, standing-charge differences and other household electricity. A lower car-charging cost does not necessarily mean a lower whole-home bill.

Energy Saving Trust: charging electric vehicles ↗