UK gallons to US gallons
1 UK gallon = 1.20095 US gallons
Type a value in UK gallons (imp gal) to get US gallons (gal) straight away. A UK gallon is larger than a US gallon, so the number goes up. Both units belong to volume, measured here against the liter.
1 imp gal = 1.2009499 gal
Formula
gal = imp gal × 1.2009499
One UK gallon is 1.2009499 US gallons, so multiply the UK gallon value by that factor. Here imp gal is the value in UK gallons and gal is the result in US gallons.
Worked example: 5 UK gallons × 1.2009499 = 6.00475 US gallons.
UK gallons to US gallons table
| UK gallons (imp gal) | US gallons (gal) |
|---|---|
| 1 imp gal | 1.20095 gal |
| 2 imp gal | 2.4019 gal |
| 3 imp gal | 3.60285 gal |
| 4 imp gal | 4.8038 gal |
| 5 imp gal | 6.00475 gal |
| 6 imp gal | 7.2057 gal |
| 7 imp gal | 8.40665 gal |
| 8 imp gal | 9.6076 gal |
| 9 imp gal | 10.8085 gal |
| 10 imp gal | 12.0095 gal |
| 15 imp gal | 18.0142 gal |
| 20 imp gal | 24.019 gal |
| 25 imp gal | 30.0237 gal |
| 30 imp gal | 36.0285 gal |
| 40 imp gal | 48.038 gal |
| 50 imp gal | 60.0475 gal |
| 60 imp gal | 72.057 gal |
| 75 imp gal | 90.0712 gal |
| 100 imp gal | 120.095 gal |
Everyday UK gallons in US gallons
| What it is | imp gal | gal |
|---|---|---|
| an imperial gallon | 1 imp gal | 1.20095 gal |
| a jerry can (about) | 5 imp gal | 6.00475 gal |
| a small car tank (about) | 10 imp gal | 12.0095 gal |
| a family car tank (about) | 15 imp gal | 18.0142 gal |
| a large tank | 40 imp gal | 48.038 gal |
Quick estimate in your head
Multiply by about 1.2. For 5 imp gal that gives 6 gal against an exact 6.00475 gal, an error of 0.1%.
Watch out for
- UK fuel economy in miles per gallon uses the imperial gallon, so UK mpg figures look about 20% better than US ones for the same car.
- A US gallon (3.785 L) is about 17% smaller than a UK gallon (4.546 L). Check which one a car manual or recipe means.
About the units
UK gallon (imp gal). The imperial gallon, exactly 4.54609 L, about 20% larger than a US gallon.
US gallon (gal). The US liquid gallon, exactly 231 cubic inches or about 3.785 L. Used for fuel in the US.
Going the other way, 1 US gallon is 0.832674 UK gallons.
Questions
How many US gallons are in 1 UK gallon?
1 UK gallon is 1.20095 US gallons, and 1 US gallon is 0.832674 UK gallons.
How do I convert UK gallons to US gallons?
Use gal = imp gal × 1.2009499. For example, 5 UK gallons × 1.2009499 = 6.00475 US gallons.
Are US and UK measures the same?
No. This page uses US customary units. A UK gallon is 4.546 L against 3.785 L in the US, and a UK pint is 568 mL against 473 mL.
How much is a large tank in US gallons?
40 imp gal is 48.038 gal.
Source for the conversion factor: NIST Handbook 44, Appendix C (units of volume).
Related conversions
- US gallons to UK gallons
- liters to US gallons
- US gallons to liters
- UK gallons to liters
- liters to UK gallons
- milliliters to US fluid ounces