# EV vs Petrol Running Cost Calculator

> Compare a year’s energy and maintenance cost of an electric car and a petrol car from your mileage, consumption and local electricity and fuel prices.

Category: Energy & environment · Applies to: Worldwide · Last updated: 2026-10-29
Interactive calculator: https://calculators.geekmidst.com/calculators/ev-vs-petrol-running-cost-calculator

Running cost per year is the distance driven times the energy used per kilometre times its price, plus maintenance. Enter both cars’ figures and your local prices to compare.

Also called: EV vs gas cost calculator, Electric vs petrol car calculator, EV savings calculator.

## Inputs
- Distance driven per year (unit km; default 15000)
- EV energy use (unit kWh/100 km; default 17)
- Charging efficiency (unit %; default 90)
- Electricity price per kWh (default 0.25)
- Petrol car fuel use (unit L/100 km; default 7)
- Petrol price per litre (default 1.80)
- EV maintenance per year (default 0; optional)
- Petrol car maintenance per year (default 0; optional)
- Currency

## Results
- EV saving per year
- EV running cost per year
- Petrol car running cost per year
- EV cost per km
- Petrol cost per km
- Electricity bought per year
- Petrol bought per year

## Formula

```
EV kWh = km × kWh/100 km ÷ 100 ÷ Charging efficiency;  EV cost = EV kWh × Price + Maintenance;  Petrol cost = km × L/100 km ÷ 100 × Price + Maintenance;  Saving = Petrol cost − EV cost
```

Where:
- km: distance per year
- Charging efficiency: share of purchased electricity stored in the battery

## Worked example
1. EV: 15,000 × 17 ÷ 100 = 2,550 kWh ÷ 0.90 = 2,833.33 kWh × 0.25 = 708.33.
2. Petrol: 15,000 × 7 ÷ 100 = 1,050 L × 1.80 = 1,890.
3. Saving = 1,890 − 708.33 = 1,181.67 a year.

**Result:** Over 15,000 km a year the EV costs 708.33 in electricity against 1,890 in petrol, saving 1,181.67.

## What the result means

The gap depends mostly on the electricity price you pay; public rapid charging can cost several times more than off-peak home charging. Use the yearly saving with the price difference between the cars to estimate a payback period.

## Assumptions and limits
- Distances in kilometres and fuel use in L/100 km.
- Prices stay constant for the year.
- Purchase price, depreciation, insurance, road tax and financing are not included.

## Questions

### My petrol car is rated in MPG. How do I convert?

L/100 km = 282.481 ÷ UK MPG, or 235.215 ÷ US MPG.

### Are EV maintenance costs really lower?

EVs have no oil changes and less brake wear, but tyres may wear faster. Enter quotes or your own records rather than assuming a figure.

## Related calculators
- [EV Charging Cost Calculator](https://calculators.geekmidst.com/calculators/ev-charging-cost-calculator)
- [Fuel Cost Calculator](https://calculators.geekmidst.com/calculators/fuel-cost-calculator)
- [Gas Mileage Calculator](https://calculators.geekmidst.com/calculators/gas-mileage-calculator)
- [Carbon Emissions Calculator](https://calculators.geekmidst.com/calculators/carbon-emissions-estimate-calculator)

Source: GM¹X CalcVerse — https://calculators.geekmidst.com/calculators/ev-vs-petrol-running-cost-calculator