Gallons to Cubic Feet Converter
Convert US gallons to cubic feet — divide by 7.481. Results update as you type; exact factors shown.
One US gallon is 0.1337 cubic feet — see the exact factor, not a rounded rule of thumb.
How the gallons to cubic feet converter works
Volumes convert through the litre (exactly 1 dm³). The US gallon is exactly 3.785411784 L (231 cubic inches); the imperial gallon is exactly 4.54609 L. A US fluid ounce is 29.5735 mL, an imperial fluid ounce 28.4131 mL; a US pint is 16 US fl oz, an imperial pint 20 imperial fl oz.
The UK is metric for most trade and science but keeps miles, pints, stone and mpg (with the imperial gallon) in daily life.
Common volume conversions
| From | To | Units |
|---|---|---|
| 1 US gal | 0.1337 ft³ | US gallon to cubic feet |
| 5 US gal | 0.6684 ft³ | US gallons to cubic feet |
| 10 US gal | 1.3368 ft³ | US gallons to cubic feet |
| 20 US gal | 2.6736 ft³ | US gallons to cubic feet |
| 50 US gal | 6.684 ft³ | US gallons to cubic feet |
| 100 US gal | 13.3681 ft³ | US gallons to cubic feet |
| 250 US gal | 33.4201 ft³ | US gallons to cubic feet |
| 500 US gal | 66.8403 ft³ | US gallons to cubic feet |
| 748 US gal | 99.9931 ft³ | US gallons to cubic feet |
| 1,000 US gal | 133.6806 ft³ | US gallons to cubic feet |
| 5,000 US gal | 668.4028 ft³ | US gallons to cubic feet |
| 10,000 US gal | 1,336.8056 ft³ | US gallons to cubic feet |
Units in this converter and their exact factors
| Unit | Symbol | One unit in litres |
|---|---|---|
| millilitre | mL | 0.001 litre |
| litre | L | 1 litre |
| cubic metre | m³ | 1,000 litre |
| teaspoon (metric) | tsp | 0.005 litre |
| tablespoon (metric) | tbsp | 0.015 litre |
| cup (metric) | cup | 0.25 litre |
| US fluid ounce | US fl oz | 0.0295735296 litre |
| US cup | US cup | 0.2365882365 litre |
| US pint | US pt | 0.473176473 litre |
| US gallon | US gal | 3.785411784 litre |
| imperial fluid ounce | imp fl oz | 0.0284130625 litre |
| imperial pint | imp pt | 0.56826125 litre |
| imperial gallon | imp gal | 4.54609 litre |
| cubic foot | ft³ | 28.316846592 litre |
FAQFrequently asked questions about volume conversion
How many cubic feet in a gallon?
0.1337 cubic feet.
What is 500 gallons in cubic feet?
66.8 cubic feet.
Where does this come up?
Tank sizing, pool volume and irrigation, where capacity is quoted in gallons but space in cubic feet.
What is a cubic foot of water?
7.48 gallons, weighing about 62.4 lb.
What is 748 gallons?
One hundred cubic feet.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Physical Laboratory (NPL) — United Kingdom's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.