Measure your real fuel economy
Official figures and real-world mileage rarely match. The most accurate method: fill the tank, reset the trip meter, drive normally, then fill up again and note the distance driven and the liters added. Divide kilometers by liters to get km/L.
| Unit | Formula | Common in |
|---|---|---|
| km/L | distance ÷ liters | Korea, Japan |
| L/100km | 100 ÷ (km/L) | Europe, Australia |
| mpg (US) | km/L × 2.352146 | United States |
For example, 520 km on 40 L is 13.0 km/L, about 7.7 L/100km, or roughly 30.6 US mpg. If you are used to mpg or L/100km and now drive in Korea, where fuel economy is quoted in km/L and fuel is priced in won per liter, this makes the numbers easy to compare.
Trip and monthly fuel cost
- The Trip cost tab takes distance, fuel economy and price per liter and returns the fuel needed and the cost. Tick round trip to double the distance.
- The Monthly cost tab takes your monthly distance and shows the monthly and yearly fuel bill, handy for budgeting a commute or comparing cars.
Tips
Fuel prices change by region, station and week, so there is no fixed default price — enter what you paid at your last fill-up. Convert miles, gallons and other units with the unit converter, and see the cost in another currency with the exchange rate calculator.