Convert US Gallon to Cubic Foot
Convert us gallons to cubic feet instantly. 1 us gallon = 0.1336805556 cubic foot — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Cubic Foot to US Gallon converter for the reverse conversion.
Units explained
US Gallon
The US liquid gallon is defined as exactly 231 cubic inches (3.785411784 liters).
Based on the English wine gallon of 231 cubic inches, retained by the US after 1824.
The primary US unit for fuel, milk and large beverage containers.
English wine gallon; US since 1824.
Cubic Foot
A cubic foot is the volume of a cube one foot on a side (28.3168 L).
Derived by cubing the international foot (0.3048 m).
Used for natural gas, refrigerators, shipping and HVAC.
1959 yard agreement.
US Gallon to Cubic Foot conversion formula
The relationship between us gallons and cubic feet:
To convert us gallons to cubic feet, multiply the value in us gallons by 0.1336805556. To reverse, multiply cubic feet by 7.4805194805.
How to use this converter
Type a value into the calculator. The result in cubic feet updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Cubic Foot to US Gallon converter for the reverse direction.
Step-by-step: convert us gallons to cubic feet
- Write down the value in us gallons (gal).
- Multiply that value by the factor 0.1336805556.
- The product is the equivalent value in cubic feet (ft³).
- To reverse, multiply the cubic foot value by 7.4805194805.
Worked examples
Example 1 — Convert 1 gal to ft³:
1 × 0.1336805556 = 0.1336805556 ft³
Example 2 — Convert 100 gal to ft³:
100 × 0.1336805556 = 13.3680555556 ft³
Real-world example — Postcard and small-object dimensions
A postcard is about 5 us gallons wide. Converting to cubic feet is essential for international postal addressing forms that ask for dimensions in different units across countries.
5 gal × 0.1336805556 = 0.6684027778 ft³
Real-world example — Ruler-scale measurements
A 30-us gallon school ruler converts cleanly to cubic feet — useful when buying a desk accessory from a retailer whose product specs use a different unit.
30 gal × 0.1336805556 = 4.0104166667 ft³
Real-world example — Hardware-scale dimensions
A 10-us gallon fastener or component is about as long as a thumbnail. Mechanics and DIY enthusiasts convert between us gallons and cubic feet daily when mixing metric and imperial tools.
10 gal × 0.1336805556 = 1.3368055556 ft³
US Gallon to Cubic Foot conversion table
Standard reference values for converting us gallons to cubic feet:
| US Gallon [gal] | Cubic Foot [ft³] |
|---|---|
| 0.01 | 0.0013368056 |
| 0.1 | 0.0133680556 |
| 1 | 0.1336805556 |
| 2 | 0.2673611111 |
| 3 | 0.4010416667 |
| 4 | 0.5347222222 |
| 5 | 0.6684027778 |
| 10 | 1.3368055556 |
| 20 | 2.6736111111 |
| 30 | 4.0104166667 |
| 40 | 5.3472222222 |
| 50 | 6.6840277778 |
| 100 | 13.3680555556 |
| 500 | 66.8402777778 |
| 1000 | 133.6805555556 |
Frequently asked questions
How many cubic feet is 1 us gallon?
How do I convert us gallons to cubic feet?
How do I convert cubic feet back to us gallons?
How many cubic feet is 100 us gallons?
Popular volume unit conversions
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Metric / SI (15 units)
US Customary (Liquid) (14 units)
US Customary (Dry) (5 units)
Imperial (UK) (14 units)
Cubic (length-derived) (4 units)
Cooking / Culinary (5 units)
Sources & references
Conversion factor (1 gal = 0.1336805556 ft³) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.