EV vs petrol calculator
Enter your monthly driving, the two running costs and the price gap — get the monthly saving and the months it takes the EV to pay it back.
| Breakdown | Value |
|---|
Estimate. The method and sources are on this page — check them against your own case before you act.
How it is calculated
The EV-versus-petrol question is two cost-per-kilometre calculations plus one payback. The car with the lower running cost is not automatically the cheaper car — the price premium decides that.
Petrol cost = km ÷ km/L × price · EV cost = km ÷ km/kWh × tariff · Payback = price premium ÷ monthly saving
Convert kilometres to litres and units
Divide monthly kilometres by mileage to get litres, and by efficiency to get kWh. Everything after this is just multiplying by the price you actually pay.
Price both energy sources
Petrol is priced per litre at the pump; electricity is priced per unit (1 unit = 1 kWh) on your bill. Fuel prices change daily and tariffs change per slab, so both are inputs with dated defaults.
Divide the price gap by the monthly saving
If the EV costs ₹1.5 lakh more and saves ₹5,300 a month, payback is about 28 months. After that the saving is real, but only if you keep the car and drive that much.
Running-cost inputs and typical values
| Item | Typical value | Why it changes |
|---|---|---|
| Petrol price | ₹100–110 per litre | Daily revision; city and state taxes differ |
| Electricity tariff | ₹6–12 per kWh | State, slab, and whether you charge at home or a public charger |
| Petrol hatchback mileage | 14–20 km/L | City traffic lowers it; highway raises it |
| Electric car efficiency | 5–8 km/kWh | Size, weather, AC use and driving style |
| Home charging units | 1 unit = 1 kWh | Charging losses add roughly 5–15% |
| Public fast charging | ₹15–25 per kWh | Much costlier than home charging |
| Price premium | ₹1–3 lakh | Battery size, segment and subsidy |
What most pages get wrong
An EV usually costs a fifth to a third per km
At ₹105 petrol, 18 km/L and ₹9 per unit, the petrol car costs ₹5.83 per km and the EV ₹1.38. The gap is large but not free — public fast charging narrows it.
Payback is a division, not a promise
Price premium divided by monthly saving gives the months to break even. Drive less, charge at public rates, or pay a smaller premium, and the number moves a lot.
Servicing and resale can reverse the answer
This compares energy cost only. EVs usually cost less to service but may depreciate differently. Add insurance and resale value before deciding.
The tariff assumption is doing the heavy lifting
Home charging at a low slab is what makes the EV cheap. If you rely on public DC fast charging at ₹18–25 per unit, the saving shrinks sharply.
Frequently asked questions
How much cheaper is an EV to run than a petrol car in India?+
How long does an EV take to pay back its higher price?+
Should I use the brochure mileage for the petrol car?+
Does the calculator include EV subsidies?+
What if I charge at a public fast charger instead of home?+
Does the calculator include servicing, insurance and resale?+
Sources, dates and a changelog.
Every number this calculator uses is either an input you control or a value from the sources below. The formula is compiled and tested at build time, so the page cannot ship with a broken calculation.
Sources
This page
- Last verified: 29 October 2026
- Next review: 29 April 2027
- Vertical: Vehicle & Transport
- Build tests: 4 passed
- Changelog: 1 entry
How we handle errors
- Spotted a mistake? Report it — we correct and log it.
- Corrections appear in the changelog below.
- Read the methodology and the disclaimer.