L/100km to MPG Converter

How to convert L/100km to mpg

L/100km is a consumption figure: fuel used over a fixed distance, where lower is better. Miles per gallon is an economy figure: distance covered on a fixed amount of fuel, where higher is better. Because one is the inverse of the other, the conversion is a division, not a multiplication. Divide 235.215 by the L/100km value for US mpg, or 282.481 for UK mpg (choose UK mpg on the Gallon switch above). To go the other way, use the mpg to L/100km converter; the fuel economy converter adds km/L to the mix.

The consequence is worth remembering: halving fuel consumption doubles mpg. A car that improves from 10 to 5 L/100km goes from 23.5 to 47 mpg. The flip also means small changes at the thirsty end matter a lot. Cutting a van from 14 to 12 L/100km saves the same 2 liters per 100 km as cutting a hatchback from 6 to 4, even though the mpg change looks far smaller (16.8 → 19.6 versus 39.2 → 58.8).

Step by step

1. Take the fuel consumption in liters per 100 km.
2. Divide 235.215 by it for US mpg (or 282.481 for UK mpg).
3. Round to one decimal place.

See it on a scale

How do you measure real fuel consumption at the pump?

Refill the tank, divide the liters added by the kilometers driven since the previous fill-up, and multiply by 100. A dashboard readout is only an estimate, so for a true figure work through these steps:

1. Fill the tank until the pump clicks off, then reset the trip odometer.
2. Drive normally until you need fuel again.
3. Fill up at the same pump if you can, and note the liters added and the kilometers on the trip meter.
4. Divide liters by kilometers and multiply by 100.

For example, 42.5 L over 610 km is 42.5 ÷ 610 × 100 = 6.97 L/100km, which converts to 33.76 US mpg. Average several tanks for a reliable number, since pumps shut off at slightly different levels. If your odometer reads miles, convert the distance with the km to miles converter first.

Do converted WLTP ratings match US EPA mpg?

Not exactly: the unit conversion is exact, but WLTP and the EPA run different test cycles, so the same model earns different official figures in each market.

Most of the world rates cars in L/100km, but the test behind the number differs. The European Union uses the WLTP procedure, which replaced the older NEDC for new cars from 2017 and 2018. Canada's official fuel consumption ratings list city, highway and combined figures in L/100 km, and Australia's Green Vehicle Guide uses L/100km as well.

Because test cycles differ, a converted WLTP figure will not match the US EPA rating for the same model exactly. Convert to compare roughly, but compare official ratings only with others from the same test. Also watch the formatting: many European documents write decimals with a comma, so “6,5 l/100 km” means 6.5. Electric cars are rated in kWh per 100 km, which is an energy figure; the energy converters help there.

Common L/100km mistakes

• Forgetting that lower is better. 5 L/100km beats 7 L/100km. With mpg it is the opposite, so double-check before you pick the “bigger” number.
• Using the wrong gallon. 6 L/100km is 39.2 US mpg but 47.1 UK mpg. British car magazines always mean imperial gallons.
• Confusing L/100km with km/L. Japan, India and much of Latin America use kilometers per liter, where higher is better. The two are linked by km/L = 100 ÷ L/100km, so 8 L/100km is 12.5 km/L.
• Averaging mpg values. To combine trips, average the L/100km figures weighted by distance, then convert the result to mpg once.