Kilometers per Liter to Miles per Gallon (US) Converter

Car and motorcycle listings in several markets quote mileage in kilometres per litre, often written kmpl or km/L. This page converts that to US mpg. If you are comparing with a British source, set the To menu to Miles per Gallon (UK):

Every extra km/L adds about 2.35 US mpg, so a high two-wheeler figure such as 50 km/L lands well above 100 mpg.

Unlike litres per 100 km, km/L and mpg measure the same kind of thing: distance travelled on a unit of fuel. So the conversion is a plain multiplication, mpg = km/L × 2.35215, and doubling one doubles the other. 10 km/L is 23.5215 mpg and 20 km/L is 47.0429 mpg.

If you also need L/100km, that is the reciprocal one: divide 100 by the km/L figure. 15 km/L is 6.6667 L/100km and 12.5 km/L is exactly 8. Set the To menu to Liters per 100 km to get it directly.

Three ways to estimate, checked against the converter:

• Multiply by 2.35: 0.09% low. 15 km/L gives 35.25 mpg.
• Multiply by 7 and divide by 3: 0.8% low. 15 km/L gives 35 mpg.
• Multiply by 2.4: 2% high. 15 km/L gives 36 mpg.

For UK mpg, multiply km/L by about 2.825 instead.

To check your own vehicle rather than an advertised figure, fill the tank, note the trip meter at the next fill, and divide the distance by the litres you put in. 420 km on a 28-litre refill is 15 km/L, which this page turns into 35.2822 US mpg. Do the same with the claimed figure and you can compare the two on one scale.

The factor is the number of litres in a US gallon divided by the number of kilometres in a mile. Both are exact by definition, 3.785411784 L and 1.609344 km, so 3.785411784 ÷ 1.609344 = 2.3521458…, which rounds to 2.35215. The converter works from those two definitions rather than a rounded copy. For UK gallons, use the imperial gallon of 4.54609 L instead: 4.54609 ÷ 1.609344 is about 2.8248. Knowing this helps when a spreadsheet needs the conversion: one column, one multiplication, no special cases.