Find your vehicle's real mileage in km per litre and litres per 100 km from distance driven and fuel used.
Fill the tank to the brim, note the odometer, drive normally, then refill to the brim and note the litres added.
The fuel used for 100 km — the lower the better. It is the inverse of km per litre.
Speed, traffic, load, tyre pressure and driving style all change it.
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