Compare the fuel economy you actually get with the figure the manufacturer advertises. Enter the rated and measured L/100km, then your annual distance and fuel price, to see the percentage gap and the extra fuel cost a year. These results are approximations for general information only. Real-world fuel economy depends on the vehicle, driving style and conditions, so treat the rated figure as a reference point, not a promise.
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How to Use the Real Fuel Economy Calculator
Enter the manufacturer's rated fuel economy, your own measured figure, your yearly distance and, optionally, the fuel price. Press Calculate to see how far apart the two figures are and what the gap costs you in fuel each year.
Reading the results
Difference is how much worse (or better) your real figure is than the rating, as a percentage.
Extra fuel per year is the additional litres the gap costs over your annual distance.
Extra fuel cost per year turns that into money using the price you entered.
A negative difference means you are beating the rated figure.
Tips
Use a full-tank-to-full-tank measurement over several fill-ups for a reliable measured figure, and compare like with like (city, highway or combined).
Features
Rated versus measured fuel economy in one view
Percentage gap and the extra litres per year
Optional extra fuel cost over your annual distance
Choose your currency and copy the result
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These results are approximations for general information only. Real-world fuel economy depends on the vehicle, driving style and conditions, so always use your own measurements and the manufacturer's data as reference points.