Imperial gallons to US gallons
Type a value in imperial gallons to see it in US gallons straight away, or type in the second box to convert back.
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How to use it
- Type the value in the imperial gallons box.
- Read the result in US gallons as you type, and pick the precision you need.
- Swap the direction to convert back, or copy the result.
How it is calculated
gal (US) = gal (imp) × 1.200949926
Multiply the value in imperial gallons by 1.200949926 to get US gallons.
Example
To convert 25 gal (imp) to US gallons: 25 × 1.200949926 = 30.0237 gal (US).
Conversion table
| Imperial gallons (gal (imp)) | US gallons (gal (US)) |
|---|---|
| 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
- Imperial gallon
- The imperial (UK) gallon is defined by UK law as exactly 4.54609 liters.
- US gallon
- The US liquid gallon is defined as 231 cubic inches, exactly 3.785411784 liters.
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 US gallons are in one imperial gallon?
1 gal (imp) = 1.20095 gal (US) exactly.
How do I convert imperial gallons to US gallons?
Use gal (US) = gal (imp) × 1.200949926. For example, 25 gal (imp) = 30.0237 gal (US).
How many imperial gallons are in one US gallon?
1 gal (US) = 0.832674 gal (imp).
What is the difference between a US gallon and an imperial gallon?
A US gallon is 3.785411784 liters and the imperial gallon used in the UK is 4.54609 liters, about 20% larger. Check where a figure comes from before converting, since US sources mean the US gallon.
How many milliliters are in a cup?
The US customary cup used in recipes is 236.5882365 mL and the metric cup is 250 mL. US nutrition labels round the cup to 240 mL, so the figure differs slightly between sources.