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Fuel Economy Calculator

MPG, L/100km, and km/L — all three, from one tank.

L/100km
7.00L/100km
km / L
14.29
MPG (US)
33.60
MPG (UK)
40.35

Typical range for most modern cars in mixed driving.

About this calc

Enter your distance and fuel used — get MPG (US), MPG (UK), L/100km, and km/L simultaneously. Works for any fill-up.

FAQ

How do you convert MPG to L/100km?
L/100km = 235.2146 / MPG (US). A car that does 30 MPG (US) uses about 7.84 L/100km.
What's the difference between US and UK gallons?
A UK gallon is ~20% larger than a US gallon (4.546 L vs 3.785 L), so MPG UK numbers are proportionally higher for the same car.
What's a good fuel economy figure?
Under 5 L/100km (~47 MPG US) is excellent. 6–9 L/100km is typical for modern petrol cars. Over 12 L/100km is thirsty for a non-performance car.