1 Imperial gallon = 4.54609 litres
The Imperial gallon is 4.54609 L, still used for UK fuel economy figures in miles per gallon even though fuel is sold by the litre.
Formula L = gal (UK) × 4.54609
Type in either field — the other updates on every keystroke. Need other units? Open the full fluid converter.
| Imperial gallon | Litre |
|---|---|
| 1 gal (UK) | 4.54609 L |
| 2 gal (UK) | 9.09218 L |
| 3 gal (UK) | 13.63827 L |
| 4 gal (UK) | 18.18436 L |
| 5 gal (UK) | 22.73045 L |
| 10 gal (UK) | 45.4609 L |
| 15 gal (UK) | 68.19135 L |
| 20 gal (UK) | 90.9218 L |
| 25 gal (UK) | 113.65225 L |
| 50 gal (UK) | 227.3045 L |
| 100 gal (UK) | 454.609 L |
| 500 gal (UK) | 2273.045 L |
| 1000 gal (UK) | 4546.09 L |
| Litre | Imperial gallon |
|---|---|
| 1 L | 0.219969 gal (UK) |
| 2 L | 0.439938 gal (UK) |
| 3 L | 0.659908 gal (UK) |
| 4 L | 0.879877 gal (UK) |
| 5 L | 1.099846 gal (UK) |
| 10 L | 2.199692 gal (UK) |
| 15 L | 3.299539 gal (UK) |
| 20 L | 4.399385 gal (UK) |
| 25 L | 5.499231 gal (UK) |
| 50 L | 10.998462 gal (UK) |
| 100 L | 21.996925 gal (UK) |
| 500 L | 109.984624 gal (UK) |
| 1000 L | 219.969248 gal (UK) |
| Situation | From | To |
|---|---|---|
| One gallon | 1 imp gal | 4.546 L |
| Two gallons | 2 imp gal | 9.092 L |
| Five gallons | 5 imp gal | 22.73 L |
| Ten gallons | 10 imp gal | 45.46 L |
| Fifteen gallons | 15 imp gal | 68.19 L |
Multiply by 4.5, which reads about 1% low.
UK fuel economy is quoted per Imperial gallon. A car rated 40 mpg (Imperial) does 33.3 mpg in US gallons.
An Imperial gallon is about 20% larger than a US gallon (4.546 L against 3.785 L), so check which one a figure uses.
The Weights and Measures Act of 1824 defined the Imperial gallon as the volume of 10 pounds of water. It is now exactly 4.54609 L.
The Imperial gallon (4.546 L) is about 20% larger than the US gallon (3.785 L). An Imperial pint is 20 fl oz (568 mL) while a US pint is 16 fl oz (473 mL).
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