EV Charging Cost Calculator
Enter battery size, charge levels and electricity price to get the cost of an EV charge.
What this tool does
The cost of a charge is the energy taken from the wall times the electricity price. Adding 60% of a 60 kWh battery is 36 kWh, which at 90% charging efficiency is 40 kWh from the wall, costing 6.00 at 0.15 per kWh and adding about 126 miles at 3.5 miles per kWh. Enter your own figures above.
Works out the energy added, the energy drawn from the wall after charging losses and the cost.
Converts it to range and a cost per mile, and compares with a petrol car.
How to use it
- Enter the battery capacity and the start and end charge percentages.
- Enter the electricity price per kWh and the charging efficiency.
- Enter your car's efficiency and its unit.
- Optionally enter a petrol car's mpg and fuel price to compare.
Why use this calculator
Costs a charge from the battery size, the start and end percentages, the electricity price and the charging losses, not just battery size times price. Charging costs vary with the tariff, the charger and how much battery you add. Charging losses mean you pay for more energy than ends up in the battery, which simple "battery times price" estimates leave out.
Why we built it
We built the EV charging cost calculator to include charging losses and to convert the charge into range and cost per mile against petrol. Check household costs with the electricity cost calculator and the fuel cost calculator.
Who this tool is for
- Electric car owners and buyers
- Anyone comparing home and public charging
- People weighing an EV against a petrol car
When to use it
- Comparing home and public charging prices.
- Deciding whether an EV would save money against petrol.
- Budgeting a road trip.
- Checking an electricity tariff for overnight charging.
How it works
Energy added = capacity × (end % − start %). Energy from the wall = energy added ÷ charging efficiency, and cost = that × the price per kWh. Range added = energy added × the car's miles per kWh. Cost per mile = cost ÷ range. For petrol: miles ÷ mpg × the price per gallon.
Example: 60 kWh battery from 20% to 80% adds 36 kWh. At 90% efficiency the wall supplies 40 kWh; at 0.15 per kWh the charge costs 6.00, adds 126 miles (3.5 miles per kWh) and costs about 0.048 a mile. A 30 mpg petrol car at 3.50 a gallon would cost 14.70 for 126 miles.
Efficiency changes with speed, temperature and load. Public chargers and time-of-use tariffs have different prices, so run it for each rate you pay.
A worked example
These are the values the calculator opens with, so you can see exactly what it does with them. Change any value on the page and the result updates; the figures below come from the same calculation.
| Input | Value |
|---|---|
| Battery capacity | 60 |
| Charge from | 20 |
| Charge to | 80 |
| Electricity price per kWh | 0.19 |
| Charging efficiency | 90 |
| Car efficiency | 3.5 |
| Efficiency unit | Miles per kWh |
| Petrol car for comparison | 30 |
| Petrol price per US gallon | 4.4 |
| Currency symbol | $ (dollar) |
With those inputs, the calculator returns:
- Cost of this charge: $7.60
- Energy added to the battery: 36 kWh
- Energy drawn from the wall: 40 kWh
- Range added: 126 miles (203 km)
- Cost per mile: $0.06
- Cost per 100 miles: $6.03
- Petrol cost for the same distance: $18.48
- Saving against petrol: $10.88
Rates and figures on this page
Figures checked on 16 October 2026. The default electricity price of 0.19 per kWh is close to the US residential average (about 18.8 cents per kWh in April 2026, from the US Energy Information Administration), and the default petrol price of 4.40 per US gallon is close to the AAA national average of about $4.41 on 1 October 2026. Public fast chargers usually cost more per kWh than home charging.
Replace both prices with your own tariff and local fuel price for a result you can rely on.
What you give it, and what you get back
| Item | Details |
|---|---|
| Battery and charge | Capacity in kWh and the start and end percentages. |
| Price and efficiency | Price per kWh and the charging efficiency. |
| Car efficiency | Miles per kWh, kWh per 100 miles, km per kWh or kWh per 100 km. |
| Output | Cost of the charge, energy added and drawn, range added, cost per mile and the petrol comparison. |
Issues you may run into
| What you see | Why it happens | What to do |
|---|---|---|
| The cost seems too low | Charging losses and fast-charger prices were not included. | Lower the efficiency and use the public price for public charging. |
| Range looks optimistic | It uses the efficiency you enter. | Use a figure measured in your usual conditions. |
| Petrol comparison missing | The comparison needs both mpg and a fuel price. | Enter both under the optional fields. |
Assumptions and limitations
- A single flat price per kWh.
- No time-of-use or standing charges.
Frequently asked questions
How much does it cost to charge an electric car?
Energy from the wall in kWh times your price per kWh. A 60 kWh battery charged from 20% to 80% takes about 40 kWh and costs 6.00 at 0.15 per kWh.
Why does charging use more energy than the battery gets?
Some energy is lost as heat in the charger and battery, commonly around 10%.
How do I find my car's efficiency?
It is on the trip computer or the maker's data. Convert it to miles per kWh or use the unit selector.
Is charging at home cheaper than a public charger?
Usually, but it depends on your tariff and the public network's price.
How does it compare with petrol?
Enter your petrol car's mpg and the fuel price and the saving is shown.
Is my information sent anywhere?
No. The calculation runs in your browser and nothing leaves the page.