EV Charging Cost Per Mile

How EV Charging Cost Per Mile works

This tool calculates the electricity expense of driving one mile in an electric vehicle. The calculation requires two figures: the vehicle's efficiency rating in miles per kilowatt-hour and the unit price of electricity. By dividing the price per kWh by the vehicle's mi/kWh efficiency, the calculator produces a cost-per-mile figure alongside scaled results for 100-mile and 1,000-mile distances.

The formula

The equation is straightforward division:

Cost per mile (£/mi) = Price per kWh (£/kWh) ÷ Efficiency (mi/kWh)

Where Price per kWh is the retail electricity rate charged by the supplier, and Efficiency is the manufacturer-stated or real-world-measured consumption expressed as miles driven per kilowatt-hour consumed.

Where this method is most accurate

The result reflects steady-state driving at the stated efficiency. Real-world consumption varies with temperature, terrain, driving style, and accessory load. Manufacturer efficiency claims typically derive from standardised test cycles (WLTP in the UK) conducted at moderate ambient temperatures. Cold weather can reduce range by 20–40 per cent; motorway speeds above 70 mph increase consumption compared to urban cycles. Charging losses—the difference between meter reading and battery capacity added—are not included in this per-mile figure.

What this tool does not do

The calculator does not account for tariff structures (off-peak rates, standing charges, or capacity fees), public fast-charging premiums, battery degradation over time, or the cost of home charger installation. It assumes the input efficiency figure is accurate; the tool performs no measurement or validation of vehicle consumption. It does not compare EV running costs to petrol or diesel equivalents, nor does it include insurance, servicing, or depreciation.

Disclaimer

This calculator is an educational mathematics tool. It produces cost estimates based solely on the numbers entered and the published division formula. It offers no advice on which vehicle to purchase, which electricity tariff to choose, or whether an EV suits a particular use case. Real-world costs depend on individual driving patterns, local electricity pricing, and vehicle condition. Users remain responsible for verifying efficiency claims and tariff details with manufacturers and suppliers.