Know your fuel economy and trip cost
Fuel is one of the largest running costs of any vehicle, and small differences in economy add up fast over a year. This calculator turns three numbers you can read off the pump and the odometer into your real fuel efficiency in litres per 100 km, plus the cost of the trip and the cost per 100 km.
How to use the calculator
Enter the distance driven since your last fill, the litres of fuel you just put in to top up, and the price per litre. The calculator returns your L/100km, the cost to travel 100 km, and the total cost of the fuel.
The formula
Fuel economy in L/100km = (litres used ÷ distance in km) × 100. Using 40 litres to travel 500 km gives (40 ÷ 500) × 100 = 8 L/100km. Lower numbers are better — the opposite of the miles-per-gallon scale, where higher is better.
What good economy looks like
As a rough guide, a hybrid car returns about 4–5 L/100km, a small petrol car 6–8, and a large SUV or 4WD 10–15. Your real figure depends heavily on how and where you drive: gentle acceleration, correct tyre pressure, less idling, and steady highway speeds all improve economy, while short cold trips, roof racks, and heavy loads all hurt it. Tracking a few tanks gives you a reliable personal average.