EV charging cost calculator for home and public chargers
This EV charging cost calculator works out what it costs to charge an electric car, scooter or bike — for one session, for a full charge and per kilometre or mile — and compares that with running a petrol or diesel car. It counts the energy lost as heat while charging, which is easy to forget and can add 5–25% to the bill.
Enter your battery size, the charge level before and after, the electricity price and where you charge. It works in rupees, pounds, dollars and euros, in km or miles, with kWh/100 km, km/kWh, mi/kWh or Wh/mi, so it suits EV charging cost questions in India, the UK, the US and elsewhere. Nothing is sent anywhere.
How to calculate EV charging cost
- Choose your currency and km or miles.
- Enter the battery capacity and the Charge from and Charge to percentages.
- Pick Where you charge to fill a typical charging loss, or type your own, then enter the electricity price per kWh and any fee or tax.
- Under Running cost and petrol comparison, enter the EV’s energy use, your monthly distance, and the fuel price and economy of the car you are comparing.
- Read the cost of the charge, the cost per km or mile and the monthly saving.
EV Charging Cost Calculator features
Charging losses included
Meter energy = battery energy ÷ (1 − loss), with presets for a household socket, a wallbox and a DC fast charger.
Public charger extras
Add a session or parking fee and tax charged on top of the per-kWh price.
Cost per km or mile
Uses the energy figure from your trip computer and the real cost of each kWh that reaches the battery.
EV vs petrol
Monthly and yearly fuel-versus-electricity comparison with a bar chart.
Any units
kWh/100 km, km/kWh, mi/kWh, Wh/mi; km/L, L/100 km, US or UK mpg; price per litre or gallon.
The EV charging cost formula
Energy into the battery = capacity × (charge to − charge from) ÷ 100. Energy drawn from the meter = battery energy ÷ (1 − charging loss). Cost = meter energy × price per kWh, plus any session fee, plus tax.
Worked example: a 30 kWh battery charged from 20% to 80% takes in 18 kWh. With a 7% loss the meter supplies 18 ÷ 0.93 = 19.35 kWh; at ₹8 per kWh that is ₹154.84, and a full 0–100% charge is about ₹258. If the car uses 14 kWh per 100 km, each km costs 0.14 × ₹8 ÷ 0.93 ≈ ₹1.20, against ₹6.67 for a petrol car doing 15 km/L on ₹100 petrol.
How much energy is lost when charging?
Charging losses depend on the charger, the current and the battery temperature. In tests of five electric cars published in August 2026, the German motoring club ADAC measured:
| How you charge | Energy lost (ADAC 2026) | Preset here |
|---|---|---|
| Household socket, 2.3 kW | 12.7–24.2% | 15% |
| Wallbox, 11 kW | 5.1–7.0% | 7% |
| DC fast charger | 5–15% (1–4% with a warm, preconditioned battery) | 10% |
Home vs public charging, and tariffs
- Home: use the per-kWh rate on your electricity bill; with slab or time-of-day tariffs, use the rate for the units your charging adds. A cheap overnight rate can cut the cost a lot.
- Public chargers: the price per kWh is usually higher, and some add tax, a session fee or idle fees. Enter what the app shows.
- Charging time: about meter energy ÷ charger power. DC charging slows down above roughly 80%, so near-full times are longer than shown.
- For your whole household bill use the electricity bill calculator; for every cost of owning the car, the cost per km calculator; for a petrol trip, the fuel cost calculator.
EV Charging Cost Calculator FAQ
How do I calculate the cost to charge an electric car?
Multiply the energy you add (battery kWh × change in charge %) by the price per kWh, then divide by (1 − charging loss). The EV charging cost calculator above also adds fees and tax.
How much does it cost to fully charge an EV?
Battery capacity ÷ (1 − loss) × price per kWh. A 30 kWh car with a 7% loss at ₹8 per kWh costs about ₹258; a 60 kWh car at £0.25 costs about £16.
Is charging an EV cheaper than petrol (or gas)?
Usually, when you charge at home: in the example above electricity costs about ₹1.20 per km against ₹6.67 for petrol. Rapid public charging narrows the gap. Enter your own prices to compare.
What is the EV charging cost per km?
Energy use per km × price per kWh ÷ (1 − loss). At 14 kWh per 100 km and ₹8 per kWh with a 7% loss it is about ₹1.20 per km.
Why does my meter show more kWh than the battery received?
Chargers and the car’s on-board charger lose some energy as heat. Losses are highest on slow household sockets and lowest on wallboxes.
Are the results exact?
No. They are estimates from the values you enter; real consumption changes with speed, weather and air-conditioning, and tariffs change often.