Gallons to Liters Converter
Type US gallons to get liters. One US gallon is exactly 3.785411784 liters.
5 gal =
18.9271L
5 US gallons is 18.9271 liters.
- 1 gal
- 3.7854 L
- 1 L
- 0.2642 gal
How this works: Method, 5 sources,
How this works
Method
Multiply US gallons by 3.785411784. This number is exact: a US gallon is 231 cubic inches by definition, and with the inch fixed at 2.54 cm, 231 cubic inches is 3,785.411784 cubic centimeters. Full method
Sources
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Changes
- Ask understands “5 ft 9 in to cm” and “2 cups of flour in grams” and answers at once, and a decimal comma (“2,5”) reads as 2.5.
- First published: 89 everyday units across ten quantities, with 58 pages for common pairs such as cm to inches and Celsius to Fahrenheit.
How to convert gallons to liters
Multiply US gallons by 3.785411784. This number is exact: a US gallon is 231 cubic inches by definition, and with the inch fixed at 2.54 cm, 231 cubic inches is 3,785.411784 cubic centimeters.
Fifteen gallons of fuel is 15 × 3.7854 = 56.78 liters. A 3 gallon water cooler bottle holds 11.36 liters, and a 55-gallon drum, filled to the brim, holds 208.2 liters.
For imperial gallons multiply by 4.54609 instead. A 5 gallon bucket in Britain, if it really is 5 imperial gallons, holds 22.7 liters, while a US 5 gallon bucket holds 18.9 liters.
liters = US gallons × 3.785411784
- One US gallon is 231 cubic inches, which NIST gives as exactly 3.785411784 liters. Source: NIST, SI units: volume.
- One imperial gallon is 4.54609 liters, about 20% more than a US gallon. Source: UK Weights and Measures Act 1985, Schedule 1.
How to estimate gallons to liters in your head
Multiply by 4, then take away 5%. Four liters per gallon is slightly generous, so trim it: 15 × 4 = 60, minus 3 is 57, against the exact 56.78. For a quick figure at the pump, “four liters a gallon, minus a bit” is close enough.
For imperial gallons, multiply by 4.5: 10 imperial gallons is about 45 liters (45.46 exactly).
Gallons to liters chart
US gallons in liters, and what the same number of imperial gallons would be.
| Gallons | Liters (US gallon) | Liters (UK gallon) |
|---|---|---|
| 0.25 | 0.9464 | 1.1365 |
| 0.5 | 1.8927 | 2.273 |
| 1 | 3.7854 | 4.5461 |
| 2 | 7.5708 | 9.0922 |
| 2.5 | 9.4635 | 11.3652 |
| 3 | 11.3562 | 13.6383 |
| 4 | 15.1416 | 18.1844 |
| 5 | 18.9271 | 22.7305 |
| 6.5 | 24.6052 | 29.5496 |
| 8 | 30.2833 | 36.3687 |
Show all 20 rowsShow fewer
| 10 | 37.8541 | 45.4609 |
| 12 | 45.4249 | 54.5531 |
| 15 | 56.7812 | 68.1913 |
| 18 | 68.1374 | 81.8296 |
| 20 | 75.7082 | 90.9218 |
| 25 | 94.6353 | 113.652 |
| 30 | 113.562 | 136.3827 |
| 40 | 151.416 | 181.8436 |
| 55 | 208.198 | 250.035 |
| 100 | 378.541 | 454.609 |
Frequently Asked Questions
How many liters are in a gallon?
A US gallon is 3.785 liters and an imperial (UK) gallon is 4.546 liters. If a source does not say which, US labels and recipes mean the US gallon.
How many liters is a half gallon of milk?
A US half gallon is 1.893 liters, just under 2 liters. A quart, a quarter of a gallon, is 0.946 liters.
How many liters does a 5 gallon bucket hold?
Five US gallons is 18.93 liters. If the bucket is sold by imperial gallons, 5 of them is 22.73 liters, so check the country of the label.
How many liters is a cubic foot of water?
A cubic foot is 28.32 liters, which is 7.48 US gallons. That is handy for sizing a tub, a pond or a fridge listed in cubic feet.