Petrol vs EV Calculator
Compare the running cost of a petrol car against an electric vehicle and see your savings per trip and per km.
Formula last reviewed 4 August 2026 · How we verify our calculators
You save with EV
- Petrol cost
- ₹667
- EV cost
- ₹120
- Petrol cost/km
- ₹7
- EV cost/km
- ₹1
Updates live as you type
Frequently asked questions
Energy used = (distance ÷ 100) × efficiency in kWh/100km, multiplied by your electricity price. For 100 km at 15 kWh/100km and ₹8/kWh, that is ₹120.
On energy cost almost always, because electricity per km is far cheaper than petrol. This tool compares running cost only — not the purchase price, battery replacement or maintenance.
Most compact EVs use roughly 12–18 kWh per 100 km. Check your model’s rated consumption, and remember home charging is far cheaper than public fast charging.
No. EVs often cost more to buy, so factor in that premium separately and divide it across your expected kilometres to judge total cost of ownership.
An EV running at a fifth the per-kilometre cost, before anything else is counted
Cover 100 km on petrol at 15 km/L and ₹100/L, and it costs (100 ÷ 15) × 100 = ₹666.67. Cover the identical 100 km on an EV rated 15 kWh/100km at ₹8/kWh, and it costs (100 ÷ 100) × 15 × 8 = ₹120 — a saving of ₹546.67, or roughly ₹6.67/km for petrol versus ₹1.20/km for the EV. Scale that per-km gap to a more typical 15,000 km driven per year, and it implies roughly ₹82,000 in annual running-cost savings from energy alone, before any purchase-price difference enters the picture.
Why the two costs are calculated so differently
Petrol cost follows distance ÷ mileage × price — straightforward multiplication once mileage is known. EV cost instead works in kWh: (distance ÷ 100) × efficiency in kWh/100km × electricity price, because EV efficiency is conventionally rated per 100 km rather than per single km the way petrol mileage is. The per-kilometre figures for both sit side by side specifically because they're the clearest, most comparable way to see the actual gap once the different units are normalized.
What this comparison deliberately leaves out
This compares running (energy) cost only. It doesn't include the EV's typically higher purchase price, battery longevity and eventual replacement cost, insurance, or maintenance — though EVs usually come out ahead on servicing too, with fewer moving parts to wear out over time. To judge whether an EV genuinely pays off overall rather than just on fuel, take the purchase price premium over an equivalent petrol car, divide it by expected kilometres driven, and compare that per-km premium against the per-km energy savings shown here. Home charging makes the EV case meaningfully stronger; relying mostly on public fast charging narrows the gap considerably.