Different countries measure fuel consumption differently. Much of Europe uses liters per 100 km (L/100km), some countries use kilometers per liter (km/L), and the US and UK use miles per gallon (MPG). That makes comparing cars or reading foreign reviews confusing. Here's how to convert between them.
Three ways to measure fuel consumption
- L/100km — how many liters a car burns per 100 km. Lower is more efficient. The common metric in much of the world.
- km/L — how many kilometers you get from one liter. Higher is more efficient.
- MPG (miles per gallon) — the US/UK measure. Also "higher is better."
Note that L/100km and km/L are inverses of each other — that's a frequent source of confusion.
The formulas
L/100km ↔ km/L:
km/L = 100 ÷ (L/100km)
L/100km = 100 ÷ (km/L)
For example, 8 L/100km = 100 ÷ 8 = 12.5 km/L.
MPG — watch out for gallons. There are two different gallons: the US gallon (3.785 L) and the UK gallon (4.546 L), so US MPG and UK MPG differ. That's another reason not to calculate this by hand.
Approximate conversion table
| L/100km | km/L | US MPG |
|---|---|---|
| 5 | 20 | ~47 |
| 7 | 14.3 | ~34 |
| 10 | 10 | ~24 |
| 12 | 8.3 | ~20 |
Converting online
To avoid confusion with "inverted" units and two kinds of gallons, use the fuel consumption converter: enter a value in any unit and get the rest instantly, with the correct US/UK gallon handling built in.
Related tools
If you also need to convert distance (miles to kilometers) or volume (gallons to liters) separately, the length converter and volume converter can help.