How is Fuel Consumption Calculated?

Formula and example of how to calculate fuel in L/100km with fuel transaction data

The following formula is used to calculate fuel consumption in litres / 100kms, the most commonly used measure of fuel consumption.


(Litres used X 100) ÷ km travelled = Litres per 100km.

The data you need for this calculation is 

Odometer at 1st fuel fill eg 1000km

Odometer ar 2nd fuel fill eg 1500km

Litres add to fill tank to max at 2nd fill (Litres used) eg 65 litres

Example a car uses 65 litres to travel 500km

(65 X 100) ÷ 500 = 13 Litres/100km