MPG to km/L Converter, US and UK Gallons
Convert miles per gallon to kilometres per litre with the exact US and UK gallon sizes. See the formula, a table of common values and why the two gallons differ.
30 MPG (US) = 12.7543 km/L
- MPG (US)
- 30
- MPG (UK)
- 36.0285
- km/L
- 12.7543
- L/100 km
- 7.84049
- mi/L
- 7.92516
- km/gal (US)
- 48.2803
Higher MPG, km/L and mi/L mean a more efficient car; a lower L/100 km means the same. L/100 km = 235.214583 ÷ MPG (US).
About the MPG to km/L Converter
This page converts miles per gallon (MPG) to kilometres per litre (km/L), the distance-per-volume unit used in India, Japan, Brazil and much of Asia and South America. Both units say how far a car travels on a fixed amount of fuel, so a higher number is better in both. The converter above opens with MPG (US) to km/L and lets you switch to MPG (UK), L/100 km and other units.
The conversion only needs two lengths: 1 mile is exactly 1.609344 km, and a gallon is either 3.785411784 litres (US) or 4.54609 litres (UK).
How to use it
Steps
- Type your MPG into Fuel economy.
- Leave From on MPG (US), or choose MPG (UK) if your car's figure comes from a UK source.
- Read the km/L result in the headline and the other units in the tiles below.
Worked examples
Example 1: US MPG
A pickup truck rated 20 MPG (US) does 20 × 0.425144 = 8.50287 km/L.
Example 2: UK MPG
A diesel estate rated 50 MPG (UK) does 50 × 0.354006 = 17.7003 km/L, which is 41.6337 MPG (US). The UK figure looks better because the imperial gallon is larger.
Example 3: a road trip
At 12 km/L a 600 km journey needs 600 / 12 = 50 litres. That is 12 × 2.35215 = 28.2 MPG (US).
MPG (US) to km/L table
| MPG (US) | km/L |
|---|---|
| 10 | 4.251 |
| 15 | 6.377 |
| 20 | 8.503 |
| 25 | 10.629 |
| 30 | 12.754 |
| 35 | 14.880 |
| 40 | 17.006 |
| 50 | 21.257 |
| 60 | 25.509 |
MPG (UK) to km/L table
| MPG (UK) | km/L |
|---|---|
| 10 | 3.540 |
| 20 | 7.080 |
| 30 | 10.620 |
| 40 | 14.160 |
| 50 | 17.700 |
| 60 | 21.240 |
| 70 | 24.780 |
Which gallon is yours
US sources, the EPA and car adverts in America use the US gallon. Sources in the United Kingdom, and historically Ireland and some Commonwealth countries, use the imperial gallon. If you pick the wrong one the answer is 20% out. When a figure has no label, assume it matches the country it came from.
Typical values
Small petrol cars manage about 35 to 45 MPG (US), which is 15 to 19 km/L. A family SUV at 25 MPG (US) is 10.6 km/L. Full-size pickups at 18 MPG (US) are 7.7 km/L, and efficient hybrids at 50 MPG (US) reach 21.3 km/L. Motorcycles and scooters often exceed 30 km/L. Real-world economy depends on speed, load, tyre pressure and weather, so the figure on the sticker is a guide, not a promise.
Quick mental estimate
Divide the MPG (US) figure by 2.35 to get km/L, or simply by 2.4 if you want an answer in your head. 36 MPG (US) divided by 2.4 is 15 km/L, and the exact answer is 15.30 km/L. For MPG (UK), divide by 2.8 instead. The estimate is within about 2%, which is good enough for comparing cars on a forecourt.
Privacy
Nothing is uploaded; every calculation runs in your browser and never leaves your device. The page keeps no history and needs no account.
Related tools
Use the full Fuel Economy Converter for all six units, the MPG to L/100 km converter for the European scale, or the Volume Converter for litres and gallons.
Frequently asked questions
How do I convert MPG to km/L?
Multiply MPG (US) by 0.425144. For example, 30 MPG (US) is 30 × 0.425144 = 12.7543 km/L. For imperial gallons multiply MPG (UK) by 0.354006 instead.
Where does 0.425144 come from?
It is one mile in kilometres divided by one US gallon in litres: 1.609344 / 3.785411784 = 0.425144. Both values are exact definitions, so the factor is exact too.
Is a higher km/L better?
Yes. km/L is distance per fuel, like MPG, so a bigger number means the car travels further on a litre. Typical petrol cars score 10 to 20 km/L and efficient hybrids reach 25 km/L or more.
Should I choose the US or the UK gallon?
Use the US gallon for American figures such as EPA ratings and the imperial gallon for UK figures. Picking the wrong one makes the answer 20% too high or too low, since 1 UK gallon is 4.54609 litres and 1 US gallon is 3.785411784 litres.
How do I convert km/L to MPG?
Multiply km/L by 2.352146 for MPG (US) or by 2.824809 for MPG (UK). So 15 km/L is 35.28 MPG (US). Use the swap button to run the converter in that direction.
Does the page store what I type?
No. Every calculation runs in your browser, so the numbers you type are never uploaded, saved, logged or shared with any server, and the page works without an account.