EV vs petrol/diesel cost calculator
Compare the energy cost of two vehicles using your own consumption, prices and distance.
Use the total distance you expect to drive in a year. It is not doubled by the round-trip setting.
EV is lower by $8.1 per 100 km
Energy and fuel cost only. No ownership, maintenance, taxes, charging-network fees, range or emissions are included.
Included
- EV wall energy and electricity price entered by you
- Petrol or diesel label, fuel economy and fuel price entered by you
- L/100 km, km/L, US mpg and imperial mpg conversions
- Cost per 100 km and 100 miles for both scenarios
- One-way or round-trip cost and annual cost from total distance
Not included
- Vehicle purchase, finance, depreciation, insurance or maintenance
- Public or home charging fees beyond the entered electricity price
- Fuel taxes, subscriptions, battery replacement or charging losses added by the app
- Emissions, range, charging time, weather, traffic, terrain, payload or driving style
What this means
The comparison puts both vehicles on the same distance basis. EV energy from the wall is multiplied by your electricity price; fuel consumption is converted to litres per 100 kilometres and multiplied by your fuel price.
Petrol and diesel are scenario labels. The calculator does not add a fuel-specific correction, tax, density or emissions estimate, so enter the efficiency and price that match the vehicle and fuel you want to compare.
A lower result means lower entered energy or fuel cost for that particular price and consumption scenario. It is not a verdict about purchase cost, ownership, maintenance, emissions or which vehicle is right for you.
Formula & worked example
EV cost per 100 km = EV kWh per 100 km × electricity price per kWh fuel cost per 100 km = fuel litres per 100 km × fuel price per litre difference = fuel cost − EV cost
EV at 18 kWh/100 km and $0.25/kWh versus petrol at 7 L/100 km and $1.80/litre
- EV cost per 100 km
- 18 × $0.25 = $4.50
- Petrol cost per 100 km
- 7 × $1.80 = $12.60
- Difference
- $12.60 − $4.50 = $8.10
With these entered values, the EV energy cost is $8.10 lower per 100 km. The result changes if either price or efficiency changes.
How this calculation works
The calculation follows the formulas, definitions and assumptions explained on this page. The references below support the method and any stated boundaries.
Official sources
- NIST — SI conversion factors — Exact kilometre-to-mile and US/imperial gallon relationships used by the comparison
- U.S. Energy Information Administration — kilowatthour definition — Energy-unit definition used for the EV input