EV Charging Cost Calculator
Calculate how much it costs to charge an electric vehicle at home or on a public charger. Enter battery size, start charge, target charge, electricity price, charging efficiency and charger power to estimate energy added, energy drawn from the charger, total cost, cost per mile and charging time.
Calculate EV charging cost
Use this for home charging, workplace charging, public AC charging or rapid charging estimates. The calculator accounts for charging losses, which means the energy taken from the wall or charger can be higher than the energy added to the battery.
Quick examples
| Battery percentage added | — |
| Estimated range added | — |
| Cost per mile | — |
| Cost per 100 miles | — |
| Price used | — |
| Charging losses | — |
How it works
The calculator works out the percentage of battery you want to add, converts that into kWh using the battery capacity, then adjusts for charging efficiency. The adjusted energy is multiplied by the electricity price to estimate the charging cost. Charger power is used to estimate charging time, while miles per kWh estimates range added and cost per mile.
Formula used
energy added = battery size × battery % added ÷ 100
energy drawn = energy added ÷ charging efficiency
charging cost = energy drawn × price per kWh + extra fees
charging time = energy drawn ÷ charger power
range added = energy added × miles per kWh
Worked example
Example: 60 kWh battery, charging from 20% to 80%
energy added = 60 kWh × 60 ÷ 100 = 36 kWh
energy drawn at 90% efficiency = 36 ÷ 0.90 = 40 kWh
cost at 24.5p/kWh = 40 × £0.245 = £9.80
So, charging from 20% to 80% costs about £9.80 at 24.5p/kWh with 90% charging efficiency.
Common mistakes
Ignoring charging losses
The charger may supply more energy than the battery stores, so cost is usually based on energy drawn from the charger.
Using usable vs gross battery size
Some manufacturers quote gross battery capacity, while the usable capacity may be slightly lower.
Assuming charger power is constant
Rapid charging speed often slows as the battery fills, especially above 80%.
Forgetting public charging fees
Some public chargers include connection fees, parking charges or overstay fees in addition to the kWh price.
Common questions
How do I calculate EV charging cost?⌄
Why does charging efficiency matter?⌄
Is public charging more expensive than home charging?⌄
Why is charging time only approximate?⌄
Sources, assumptions and disclaimer
This calculator is for general EV charging cost estimation. It uses the battery size, charge percentages, efficiency, charger power and electricity price you enter. It does not fetch live tariffs or charging network prices and does not guarantee actual charging cost or charging time.
- Battery size: use usable battery capacity where possible, not only the advertised gross capacity.
- Charging efficiency: home and public charging can have losses due to heat, onboard charger efficiency and vehicle systems.
- Charging time: the calculator assumes average charger power, but rapid charging power can taper as the battery fills.
- Price per kWh: use your home tariff or the public charger price shown by the network.
- Disclaimer: this is an estimate only and is not financial, tariff, vehicle, battery-health or charging-network advice.