Convert Kilometers per Gallon (US) to Miles per Gallon (UK)
Kilometer per Gallon (US) (km/gal) to Mile per Gallon (UK) (mpg (UK)) fuel-economy conversion — enter any value below to get an instant result, or use the table for common values.
Results from this calculator are estimates provided for general informational purposes only, based on formulas, rates, and standards commonly accepted as of 2026. Figures may differ slightly from other calculators or professional sources due to rounding methods, differing assumptions, or regional regulations, and rules may change over time. Always consult a qualified professional — such as a financial advisor, healthcare provider, or other relevant specialist — before making decisions based on these results.
Result
1 km/gal = 0.74623569 mpg (UK)
1 Kilometer per Gallon (US) = 0.74623569 Miles per Gallon (UK)
1 Mile per Gallon (UK) = 1.3400592 Kilometers per Gallon (US)
1 km/gal in every supported unit
Conversion chart: Kilometer per Gallon (US) to Miles per Gallon (UK)
Conversion table
| Kilometer per Gallon (US) (km/gal) | Mile per Gallon (UK) (mpg (UK)) |
|---|---|
| 0.01 km/gal | 0.0074623569 mpg (UK) |
| 0.1 km/gal | 0.074623569 mpg (UK) |
| 1 km/gal | 0.74623569 mpg (UK) |
| 2 km/gal | 1.4924714 mpg (UK) |
| 3 km/gal | 2.2387071 mpg (UK) |
| 5 km/gal | 3.7311784 mpg (UK) |
| 10 km/gal | 7.4623569 mpg (UK) |
| 20 km/gal | 14.924714 mpg (UK) |
| 50 km/gal | 37.311784 mpg (UK) |
| 100 km/gal | 74.623569 mpg (UK) |
| 1000 km/gal | 746.23569 mpg (UK) |
Kilometer per Gallon (US) (km/gal)
Definition: The distance in kilometers a vehicle travels on one US gallon of fuel — a mixed-unit measure bridging metric distance with US-gallon fuel purchases.
History: Used in markets that measure road distance in kilometers but historically purchased or referenced fuel volume in US gallons, such as parts of Latin America influenced by US vehicle marketing.
Current use: Seen occasionally in Latin American and Caribbean markets where both metric distance and US-gallon fuel references coexist in everyday use.
Mile per Gallon (UK) (mpg (UK))
Definition: The distance in miles a vehicle travels on one imperial (UK) gallon of fuel — numerically higher than US mpg for the same vehicle because the imperial gallon (4.546 L) is larger than the US gallon.
History: Rooted in the British imperial system of weights and measures standardized in 1824, carried into the motor age as the UK's default fuel-economy figure.
Current use: Still the everyday fuel-economy unit quoted by UK, Irish, and Canadian drivers and some vehicle manufacturers' UK-market literature, despite the UK selling fuel by the liter at the pump.
Supported Units
| Unit | Symbol | Direction |
|---|---|---|
| Meter per Liter | m/L | Higher is more efficient |
| Kilometer per Liter | km/L | Higher is more efficient |
| Mile per Liter | mi/L | Higher is more efficient |
| Mile per Gallon (US) | mpg | Higher is more efficient |
| Mile per Gallon (UK) | mpg (UK) | Higher is more efficient |
| Kilometer per Gallon (US) | km/gal | Higher is more efficient |
| Nautical Mile per Gallon (US) | nmi/gal | Higher is more efficient |
| Liter per 100 Kilometers | L/100km | Lower is more efficient |
| Gallon (US) per Mile | gal/mi | Lower is more efficient |
| Gallon (UK) per Mile | gal/mi (UK) | Lower is more efficient |
About These Parameters
- Value
- The fuel-economy figure you want to convert, expressed in the "From" unit. Accepts decimals.
- From Unit
- The fuel-economy unit your input value is currently measured in — a "distance per volume" unit like mpg or km/L, or a "volume per distance" unit like L/100km.
- To Unit
- The unit you want the result converted into. Use the swap button to flip From and To instantly.
How Fuel Consumption Conversion Works
The Formula
For two "distance per volume" units (like mpg and km/L), conversion is a simple multiplication — the same shape used by every other converter on this site:
result = value × (factor of "From" unit ÷ factor of "To" unit)
But converting to or from a "volume per distance" unit (L/100km, gallons per mile) requires an extra reciprocal step, because those units run backwards — a bigger number means worse economy, not better:
L/100km = 100,000 ÷ (value in meters per liter)
For Kilometer per Gallon (US) → Mile per Gallon (UK): 1 km/gal = 0.74623569 mpg (UK).
Why "Bigger Is Better" Flips Direction
Miles per gallon and kilometers per liter both ask "how far does my fuel take me?" — a higher number is a more efficient vehicle. Liters per 100 km and gallons per mile ask the opposite question, "how much fuel does my trip cost?" — here a LOWER number is more efficient. The two framings are mathematical reciprocals of each other, not simple multiples, which is why a linear unit converter alone can't handle this category — it has to know which units run in which direction.
US mpg vs. UK mpg
"Miles per gallon" means two different things depending on the country: the US gallon is about 3.785 liters, while the imperial (UK) gallon is about 4.546 liters — roughly 20% larger. A car with an identical real-world fuel economy will show a noticeably higher mpg figure in the UK than in the US simply because the UK gallon holds more fuel, not because the car is more efficient.
Example
A car rated at 30 miles per gallon (US) converts to about 7.8404861 L/100km and about 12.754311 km/L — notice the L/100km figure is smaller for a more efficient car, while the km/L figure is larger, because they measure efficiency in opposite directions.
Frequently Asked Questions
How many Miles per Gallon (UK) are in 1 Kilometer per Gallon (US)?
1 Kilometer per Gallon (US) (km/gal) equals exactly 0.74623569 Miles per Gallon (UK) (mpg (UK)).
Why is a lower L/100km number better, while a higher mpg number is also better?
They measure fuel economy from opposite directions. Mpg and km/L ask how far a fixed amount of fuel goes (more distance = more efficient), while L/100km asks how much fuel a fixed trip costs (less fuel = more efficient). The two scales are reciprocals of each other, not simple multiples.
Is a US gallon the same as a UK gallon?
No. The US liquid gallon is about 3.785 liters, while the UK imperial gallon is about 4.546 liters — roughly 20% larger. This means US mpg and UK mpg figures for the identical vehicle are not directly comparable without converting.
How accurate are these conversions?
Every conversion factor used here is the exact, mathematically derived relationship between the distance and volume units involved (e.g. 1 US gallon = exactly 3.785411784 liters) — results are limited only by floating-point display precision, not by rounded conversion constants.