Fuel Cost Per Km Calculator

How it is calculated

Consumption is entered in litres per 100 km, and the price is per litre. The tool computes cost per 100 km = consumption × price and cost per km = consumption ÷ 100 × price. Money is shown rounded to two decimals in the tool's default currency, so a cost per km of a few cents is displayed to the cent only; the cost per 100 km figure keeps more of the detail and is better for comparing two cars. A price of zero is accepted and gives zero cost, while a negative price or a consumption of zero or less returns no result. Use the price you actually pay per litre, and keep the litre unit: prices per gallon or consumption in miles per gallon need converting first.

Common mistakes

• Entering miles per gallon in the consumption box. The field expects litres per 100 km, where a lower number is better, the opposite of mpg.
• Typing the price per gallon or per 100 litres instead of per litre, which makes the result several times too large or small.
• Using the figure from the car's brochure as if it were real life. Test-cycle consumption is usually lower than what you get in winter, with a roof box or in city traffic, so use your own tank-to-tank figure.
• Comparing two cars on the rounded cost per km. The rounding to cents hides differences, so compare the cost per 100 km instead.
• Forgetting that this covers fuel only, with no servicing, tyres, insurance or depreciation.