A 450 km trip in a car that uses 6.8 L/100 km burns 30.6 litres and costs $53.55 in fuel at 1.75 per litre. That is $0.12 per kilometre.
The method
Litres used = distance ÷ 100 × consumption per 100 km. Here 450 ÷ 100 × 6.8 = 30.6 litres. Multiply by the price per litre to get $53.55.
Cost per kilometre is consumption ÷ 100 × price, so $0.12 here, or $11.90 per 100 km. It is a handy figure for any distance.
What moves the total
Consumption matters as much as distance. The same trip in a car that uses 9.5 L/100 km costs $74.81. Highway speed, luggage, roof boxes and air conditioning all raise real consumption above the brochure figure.
Use your own average from the last few tanks rather than the manufacturer's number.
Sharing the cost
Fuel is only part of the bill, since tolls and parking come on top. If three people share this fuel cost, each pays $17.85. The table gives the fuel for other distances.
| Distance (km) | Litres | Fuel cost |
|---|---|---|
| 200 | 13.6 | $23.80 |
| 450 | 30.6 | $53.55 |
| 800 | 54.4 | $95.20 |
| 1200 | 81.6 | $142.80 |
FAQ
How do I convert miles per gallon to L/100 km?+
Divide 235.2 by the miles per gallon (US) to get litres per 100 km. 35 mpg is about 6.7 L/100 km.
Should I add a margin to the estimate?+
A margin of 10% covers traffic, detours and a heavier load. Tolls, parking and wear are not included.