Global Fuel CalculatorFuel Consumption Calculator — L/100km, km/L and Fuel Usage
This fuel consumption calculator (you may also know it as a fuel usage calculator) turns two numbers — distance traveled and fuel used — into a complete picture of your vehicle’s fuel usage: L/100km, km/L, US MPG and imperial MPG all at once, plus fuel cost per km and per mile. It is built for any vehicle, from a city hatchback to a motorcycle, and works the same way regardless of which units your odometer or fuel pump uses.
Fuel consumption and fuel economy are the same underlying figure looked at from opposite ends: consumption asks how much fuel a fixed distance costs you, economy asks how far a fixed amount of fuel takes you. Because different countries default to different answers to that question, this calculator computes every standard from one input rather than making you convert by hand.
Work out your numbers
The fuel consumption formula
Fuel consumption is fuel used divided by distance travelled. Per kilometre that is L/km, but the figure is so small that it is normally scaled up: L/100km = fuel used in litres ÷ distance in km × 100. Use × 10 instead for consumption per 10 km, or divide by miles to get litres per mile.
A car that used 42 litres over 520 km burned 42 ÷ 520 × 100 = 8.08 L/100km. Fuel economy is simply the reciprocal, distance ÷ fuel, so the same trip is 12.38 km/L. That is why every number on this page comes from one entry: they are the same measurement written two ways.
The calculator works from your own figures, not a car-model database. That is deliberate: a model average cannot know your roads, speed or load, so your tank-to-tank number is usually the more honest one.
Common questions
How do I calculate fuel consumption or work out petrol usage?
Fill the tank, reset the trip meter (or note the odometer), drive normally for a tank, then fill up again to the same cut-off point. Divide the litres it took to refill by the kilometres on the trip meter, then multiply by 100 — that is your L/100km. This calculator does that arithmetic for you and shows km/L and MPG from the same numbers.
How do I calculate km per litre?
Divide the kilometres you drove by the litres of fuel you used. Two hundred and forty kilometres on twenty litres is 240 divided by 20, which is 12 km/L. It is the reciprocal of L/100km scaled by one hundred, so the calculator shows both from a single entry.
How do I make a fuel consumption estimate for a trip?
Multiply your L/100km by the distance in kilometres and divide by 100. At 8 L/100km, a 450 km trip needs about 36 litres. In miles and gallons, divide the distance by your MPG. This calculator does the same thing with its planned trip box.
How do I calculate cost per km?
Divide your total fuel cost for a trip by the distance covered. This calculator does it automatically: enter your price per litre or gallon alongside distance and fuel used, and cost per kilometre and cost per mile appear in the results alongside your consumption figures.
Does this work for diesel and CNG as well as petrol?
Yes. The arithmetic does not care what the fuel is — only how much of it you used and what it cost. Diesel, petrol and CNG (entered by weight rather than volume) all produce a correct result.
What is the average fuel consumption for a car?
Most petrol cars land somewhere between 6 and 10 L/100km in mixed driving, which is roughly 39 to 24 MPG in US terms. Small hatchbacks sit at the low end and SUVs and trucks at the high end. Your own number matters more than any average, and our guide to average fuel consumption has a full table.