Miles per US gallon to miles per imperial gallon
Type a value in miles per US gallon to see it in miles per imperial gallon straight away, or type in the second box to convert back.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Type the value in the miles per US gallon box.
- Read the result in miles per imperial gallon as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
mpg (UK) = mpg (US) × 1.200949926
Multiply the value in miles per US gallon by 1.200949926 to get miles per imperial gallon.
Example
To convert 25 mpg (US) to miles per imperial gallon: 25 × 1.200949926 = 30.0237 mpg (UK).
Conversion table
| Miles per US gallon (mpg (US)) | Miles per imperial gallon (mpg (UK)) |
|---|---|
| 1 | 1.20095 |
| 2 | 2.4019 |
| 3 | 3.60285 |
| 5 | 6.00475 |
| 10 | 12.0095 |
| 20 | 24.019 |
| 25 | 30.0237 |
| 50 | 60.0475 |
| 100 | 120.095 |
| 250 | 300.237 |
| 500 | 600.475 |
| 1,000 | 1,200.95 |
About the units
- Mile per US gallon
- Miles traveled on one US gallon of 3.785411784 liters, the standard in the United States. One mile is exactly 1.609344 km.
- Mile per imperial gallon
- Miles per imperial gallon of 4.54609 liters, used in the United Kingdom. It reads higher than US mpg for the same car because the gallon is larger.
Limits and caveats
- Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
- Both unit factors are exact by their official definitions.
Questions about this tool
How many miles per imperial gallon are in one mile per US gallon?
1 mpg (US) = 1.20095 mpg (UK) exactly.
How do I convert miles per US gallon to miles per imperial gallon?
Use mpg (UK) = mpg (US) × 1.200949926. For example, 25 mpg (US) = 30.0237 mpg (UK).
How many miles per US gallon are in one mile per imperial gallon?
1 mpg (UK) = 0.832674 mpg (US).
Why is mpg to L/100 km not a simple multiplication?
The units are reciprocal: one is distance per fuel, the other fuel per distance. You divide about 235.215 by the US mpg value, so 30 mpg is about 7.84 L/100 km.
Why do US and UK mpg differ?
The imperial gallon is 4.54609 L and the US gallon is 3.785411784 L, so the same car shows about 20% more miles per gallon in UK figures.