MPG to km/L Calculator
Convert miles per gallon to kilometres per litre instantly. Supports US MPG, UK (Imperial) MPG, L/100km, and km/L — with a full fuel efficiency breakdown and comparison table.
MPG to km/L Converter
Enter any fuel efficiency figure to convert across all units
Enter miles per gallon using US gallons (1 US gallon = 3.785 L)
Conversion Results
Fuel efficiency across all units
Enter a fuel efficiency value and click Convert to see all unit conversions and your efficiency rating.
MPG Conversion FAQ
Everything you need to know about converting between MPG, km/L, and L/100km.
To convert US MPG to km/L, multiply by 0.4251. For UK MPG, multiply by 0.3540. For example, 30 US MPG = 30 × 0.4251 = 12.75 km/L. This calculator does it instantly for either gallon type.
A US gallon is 3.785 litres, while a UK (Imperial) gallon is 4.546 litres. This means UK MPG figures are always higher than US MPG for the same vehicle. A car rated at 40 UK MPG is equivalent to approximately 33.3 US MPG.
km/L (kilometres per litre) measures how far a vehicle travels on one litre of fuel. L/100km measures how much fuel is needed to travel 100 km. They are reciprocals: L/100km = 100 ÷ km/L. A more fuel-efficient car has a higher km/L but a lower L/100km.
A fuel-efficient petrol car typically achieves 15–20 km/L (35–47 US MPG). Hybrid vehicles can reach 20–30 km/L. Standard family cars average around 12–15 km/L (28–35 US MPG). SUVs and larger vehicles often fall below 10 km/L.
To convert L/100km to US MPG, divide 235.21 by the L/100km figure. To convert to UK MPG, divide 282.48 by the L/100km figure. For example, 7 L/100km = 235.21 ÷ 7 ≈ 33.6 US MPG.
Different regions use different standards. The US and UK traditionally use MPG (miles per gallon), though with different gallon sizes. Most of Europe, Australia, and Asia use L/100km or km/L. Japan commonly uses km/L. The EU mandates L/100km for official fuel economy ratings.