km/L
0
Converted fuel economy
Convert MPG to km/L — and km/L to MPG — instantly for US and UK gallons
Free bidirectional fuel economy converter supporting US MPG, Imperial MPG, and km/L. Includes L/100km and full reference chart for 2026.
Accurate fuel efficiency conversion for vehicles, fleet management, and international travel in 2026
The US gallon (3.785 L) and the UK Imperial gallon (4.546 L) are different volumes — so the same MPG figure means different fuel efficiencies depending on the country. This converter handles both correctly, letting you select US or UK gallons before converting to km/L.
Every conversion shows km/L, L/100km, US MPG, and Imperial MPG simultaneously. This makes it easy to compare vehicles across markets — whether reading a US car review, a European spec sheet, or an Australian fuel economy label — all from a single input.
Essential for buying imported vehicles, comparing international car reviews, calculating fuel costs for road trips across countries, fleet fuel management, and understanding manufacturer economy claims. Covers all common real-world fuel efficiency ranges in 2026.
Select direction, choose US or UK gallon, then enter your value
Miles per gallon (MPG) is the standard fuel economy measurement in the United States and United Kingdom, expressing how many miles a vehicle can travel on one gallon of fuel. Kilometres per litre (km/L) is the equivalent metric measure used in Japan, Australia, Latin America, and parts of Asia. Because the US gallon (3.78541 L) and the UK Imperial gallon (4.54609 L) are different volumes, the same MPG number means different fuel efficiencies depending on the country — so selecting the correct gallon type is essential for accurate conversion.
The conversion uses the exact defined relationships: 1 mile = 1.609344 km, 1 US gallon = 3.78541 L, and 1 UK gallon = 4.54609 L. For example, 30 US MPG equals approximately 12.75 km/L, while 30 UK MPG equals approximately 10.62 km/L. Europe primarily uses litres per 100 km (L/100km) — a consumption-based measure rather than a distance-based one — which this converter also calculates. For other converters, see the atmospheres to pascals converter.
Note: 30 US MPG ≠ 30 UK MPG — the UK Imperial gallon is 20% larger than the US gallon. Always confirm gallon type when comparing international specifications.
Converting MPG to km/L requires knowing which gallon your MPG figure refers to. US car specs always use US gallons; UK and Australian specs historically used Imperial gallons (though Australia now uses L/100km). Follow the steps below for a quick manual conversion.
The UK Imperial gallon = 4.54609 litres, which is approximately 20% larger than the US gallon (3.78541 litres). This means a car rated at 40 UK MPG achieves better real-world economy than a car rated at 40 US MPG. When comparing international vehicle specifications, always confirm the gallon standard used to avoid a 20% calculation error.
Switch between US and UK gallon tables below. Desktop shows the full table including L/100km; on mobile use the card view for easy reading.
| US MPG | km/L | L/100km | UK MPG | Efficiency Rating |
|---|---|---|---|---|
| 10 MPG | 4.25 km/L | 23.52 L/100km | 12.01 UK MPG | Very Poor |
| 15 MPG | 6.38 km/L | 15.68 L/100km | 18.01 UK MPG | Poor |
| 20 MPG | 8.50 km/L | 11.76 L/100km | 24.02 UK MPG | Below Average |
| 25 MPG | 10.63 km/L | 9.41 L/100km | 30.02 UK MPG | Average |
| 30 MPG | 12.75 km/L | 7.84 L/100km | 36.03 UK MPG | Good |
| 35 MPG | 14.88 km/L | 6.72 L/100km | 42.03 UK MPG | Good |
| 40 MPG | 17.01 km/L | 5.88 L/100km | 48.04 UK MPG | Very Good |
| 45 MPG | 19.13 km/L | 5.23 L/100km | 54.04 UK MPG | Excellent |
| 50 MPG | 21.26 km/L | 4.70 L/100km | 60.05 UK MPG | Excellent |
| 55 MPG | 23.38 km/L | 4.28 L/100km | 66.05 UK MPG | Hybrid/EV Range |
| 60 MPG | 25.51 km/L | 3.92 L/100km | 72.06 UK MPG | Hybrid/EV Range |
| 70 MPG | 29.76 km/L | 3.36 L/100km | 84.07 UK MPG | Hybrid/EV Range |
| 80 MPG | 34.01 km/L | 2.94 L/100km | 96.08 UK MPG | Hybrid/EV Range |
| 100 MPG | 42.51 km/L | 2.35 L/100km | 120.09 UK MPG | PHEV / EV Equivalent |
| UK MPG | km/L | L/100km | US MPG | Efficiency Rating |
|---|---|---|---|---|
| 10 UK MPG | 3.54 km/L | 28.25 L/100km | 8.33 US MPG | Very Poor |
| 15 UK MPG | 5.31 km/L | 18.83 L/100km | 12.49 US MPG | Poor |
| 20 UK MPG | 7.08 km/L | 14.12 L/100km | 16.65 US MPG | Below Average |
| 25 UK MPG | 8.85 km/L | 11.30 L/100km | 20.82 US MPG | Below Average |
| 30 UK MPG | 10.62 km/L | 9.42 L/100km | 24.98 US MPG | Average |
| 35 UK MPG | 12.39 km/L | 8.07 L/100km | 29.15 US MPG | Good |
| 40 UK MPG | 14.16 km/L | 7.06 L/100km | 33.31 US MPG | Good |
| 45 UK MPG | 15.93 km/L | 6.28 L/100km | 37.48 US MPG | Very Good |
| 50 UK MPG | 17.70 km/L | 5.65 L/100km | 41.64 US MPG | Excellent |
| 55 UK MPG | 19.47 km/L | 5.13 L/100km | 45.81 US MPG | Excellent |
| 60 UK MPG | 21.24 km/L | 4.71 L/100km | 49.97 US MPG | Excellent |
| 70 UK MPG | 24.78 km/L | 4.04 L/100km | 58.30 US MPG | Hybrid/EV Range |
| 80 UK MPG | 28.32 km/L | 3.53 L/100km | 66.63 US MPG | Hybrid/EV Range |
| 100 UK MPG | 35.40 km/L | 2.82 L/100km | 83.29 US MPG | PHEV / EV Equivalent |
The US gallon = 3.78541 litres and the UK Imperial gallon = 4.54609 litres. The UK gallon is 20.09% larger. This is why UK MPG figures always appear higher than US MPG for the same vehicle — 40 UK MPG = 33.3 US MPG. Always check the source country when reading MPG specs.
Australia, Europe, and most of the world use litres per 100 kilometres (L/100km) as the fuel consumption standard. Unlike MPG (where higher = better), L/100km is a consumption figure — a lower number means better economy. A typical petrol car averages 7–10 L/100km in 2026.
A modern petrol city car achieves around 35–45 US MPG (14.9–19.1 km/L, 5.2–6.7 L/100km). A hybrid like the Toyota Prius reaches approximately 52 US MPG (22.1 km/L, 4.5 L/100km). Full EVs are rated in MPGe — miles per gallon equivalent — for energy comparison.
Japan, South Korea, and many Latin American countries use km/L as their primary fuel economy measure. A fuel-efficient Japanese city car typically achieves 15–20 km/L. Converting Japanese or Korean car specs to US or UK MPG for comparison requires this converter to account for the different gallon volumes.
Electric vehicles use miles per gallon equivalent (MPGe) or Wh/km for efficiency. The EPA defines 1 gallon of petrol = 33.7 kWh of energy. A Tesla Model 3 achieves around 141 MPGe (60 km/L equivalent). When converting EV specs to km/L, use the same MPGe-to-km/L formula as conventional MPG.
Converting MPG to km/L enables direct fuel cost comparison. If petrol costs $1.85/L and your car does 12 km/L, fuel cost = $1.85 ÷ 12 = $0.154/km. Knowing your km/L figure lets you instantly estimate refuelling costs for any trip, regardless of the MPG rating on the manufacturer's spec sheet.
This converter is essential for anyone comparing vehicles, planning road trips, or managing fuel costs across countries that use different fuel economy measurement standards in 2026.
The USA uses US MPG, the UK historically used Imperial MPG (now also L/100km), Europe uses L/100km, and Japan/Australia use km/L. All measure the same thing — distance per unit of fuel — but with different gallons and units, making conversion essential for international comparisons.
Area Converter →Electric vehicles use kWh/100km (energy per distance) or miles per kWh in addition to MPGe (miles per gallon equivalent). The EPA defines 1 gallon of petrol = 33.7 kWh. Converting between these units helps compare EVs and combustion vehicles on equivalent energy consumption terms.
Energy Converter →Explore our full suite of free unit converters covering length, mass, area, pressure, energy, and time — all fully mobile friendly and updated for 2026 international standards and definitions.
Time Converter →