myevnumbers
UK EV charging calculator

What will this charge really cost?

Estimate energy, cost, time, range added and regular charging spend. Everything runs privately in your browser.

Charge details

Choose Home for a wallbox, three-pin plug or destination AC charger. Choose Public for a rapid or other pay-per-use public charger; this selects the matching price and vehicle charge-rate profile.
The capacity the car actually lets you use, in kWh—not the larger gross figure sometimes advertised. Find “usable battery capacity” in the vehicle specification; for example, enter 60 for 60 kWh.
The battery percentage shown by the car when charging begins. For example, enter 20 if the dashboard shows 20%.
The percentage you want the charger to stop at. 80% is a common everyday limit; use 100% when planning a full charge.
Your electricity unit price in pence per kWh. Use the rate that applies while you will charge, from your tariff or bill—not the daily standing charge.
The charger network’s price in pence per kWh, shown in its app or on the charger. Enter 65 for 65p/kWh.
The maximum power the charger can supply. Typical home chargers are 7.4 kW; public chargers may be 50, 150 or 350 kW.
Advanced
The fastest rate your EV can accept for this charge type. Use its maximum AC rate at home or maximum DC rate at a rapid charger.
Some electricity is lost between the charger and battery. Keep 10% if unsure; cold weather and slow charging can alter it.
How many miles the car travels per kWh. Use the car’s recent average if available; 3.5 mi/kWh is a reasonable starting estimate.
How many similar charges you expect in a normal week. This is used only for the monthly and annual cost estimates.

How to calculate the cost of charging an electric car

What this calculator includes

The estimate uses the change in battery percentage, usable battery capacity, charging losses and your electricity price. It also limits charging speed to the lower of the charger output and the rate your vehicle can accept.

kW and kWh are different

kW is charging power—the speed electricity is delivered. kWh is energy—the amount stored or bought. A 7.4 kW home charger does not add 7.4 kWh instantly; it can deliver roughly that amount of energy in an hour before losses.

Example

Charging a 60 kWh usable battery from 20% to 80% adds 36 kWh to the battery. With 10% losses, the electricity drawn from the grid will be higher. Enter your actual tariff price to see the estimated bill.

Explore the other UK EV tools

Check whether a charge fits your off-peak window, estimate real-world range, compare annual EV and fuel costs, or allow for rapid-charging taper with the charging-time calculator.

Frequently asked questions

Should I enter gross or usable battery capacity?

Use usable capacity: the energy the car makes available for driving. It is often slightly lower than the gross battery figure advertised by the manufacturer.

Why is grid energy higher than battery energy?

Charging is not perfectly efficient. Heat, battery conditioning and power conversion mean the charger must supply more energy than reaches the battery.

Are the results exact?

No. They are planning estimates. Actual cost and time vary with battery temperature, state of charge, charger performance, vehicle limits and tariff rules.