How to convert miles per imperial gallon to miles per gallon
Formula: mpg = mpg (UK) × 0.832674
Worked example: 45 mpg (UK) → 45 × 0.832674 = 37.4703 mpg
Multiply US mpg by 1.20095 to get UK mpg, because the imperial gallon is larger. A car rated 30 mpg in the US shows about 36 mpg in a British review, with exactly the same consumption.
Miles per imperial gallon to miles per gallon conversion chart
| Miles per imperial gallon (mpg (UK)) | Miles per gallon (mpg) |
|---|---|
| 15 mpg (UK) | 12.4901 mpg |
| 20 mpg (UK) | 16.6535 mpg |
| 25 mpg (UK) | 20.8169 mpg |
| 30 mpg (UK) | 24.9802 mpg |
| 35 mpg (UK) | 29.1436 mpg |
| 40 mpg (UK) | 33.307 mpg |
| 45 mpg (UK) | 37.4703 mpg |
| 50 mpg (UK) | 41.6337 mpg |
| 55 mpg (UK) | 45.7971 mpg |
| 60 mpg (UK) | 49.9605 mpg |
| 70 mpg (UK) | 58.2872 mpg |
What is a mile per imperial gallon?
UK mpg use the imperial gallon of 4.546 liters, 20% larger than the US gallon. The same car therefore shows a higher figure in Britain: 40 UK mpg is only about 33 US mpg.
What is a mile per gallon?
Miles per US gallon are the fuel economy unit of US window stickers and EPA ratings. Higher is better. Because it is a distance per volume, savings are not linear: going from 10 to 20 mpg saves far more fuel than going from 30 to 40 mpg.