Gaugewise / MPG to L/100km
Conversion
Converts US MPG, UK MPG, litres per 100km and km per litre — all from one input, updated live.
| US MPG | L/100km | km/L | UK MPG |
|---|---|---|---|
| 20 | 11.76 | 8.51 | 24.02 |
| 25 | 9.41 | 10.63 | 30.02 |
| 30 | 7.84 | 12.76 | 36.03 |
| 35 | 6.72 | 14.88 | 42.03 |
| 40 | 5.88 | 17.01 | 48.04 |
| 50 | 4.70 | 21.27 | 60.05 |
How do I convert MPG to L/100km?
Divide 235.214 by the US MPG value. For UK (Imperial) MPG, divide 282.481 by the UK MPG value instead — the two use different-sized gallons, so the formulas aren't interchangeable.
Why are US MPG and UK MPG different for the same car?
A US gallon is about 3.785 litres; a UK (Imperial) gallon is about 4.546 litres. Because the UK gallon holds more fuel, the same car shows a higher MPG number under the UK measure — it's not a real efficiency difference, just a different-sized unit.
Is a lower L/100km number better?
Yes. L/100km measures fuel used per fixed distance, so lower means better efficiency — it moves in the opposite direction from MPG, where higher is better.
A conversion is just a number. If you want to know what your fuel economy actually costs you this year — and how it compares to an EV — use the fuel cost calculator.