Convert Cubic Feet to Gallons (US)
Cubic Foot (ft³) to Gallon (US) (gal) unit conversion — enter any value below to get an instant result, or use the table for common values.
Results from this calculator are estimates provided for general informational purposes only, based on formulas, rates, and standards commonly accepted as of 2026. Figures may differ slightly from other calculators or professional sources due to rounding methods, differing assumptions, or regional regulations, and rules may change over time. Always consult a qualified professional — such as a financial advisor, healthcare provider, or other relevant specialist — before making decisions based on these results.
Result
1 ft³ = 7.4805195 gal
1 Cubic Foot = 7.4805195 Gallons (US)
1 Gallon (US) = 0.13368056 Cubic Feet
1 ft³ in every supported unit
Conversion chart: Cubic Foot to Gallons (US)
Conversion table
| Cubic Foot (ft³) | Gallon (US) (gal) |
|---|---|
| 0.01 ft³ | 0.074805195 gal |
| 0.1 ft³ | 0.74805195 gal |
| 1 ft³ | 7.4805195 gal |
| 2 ft³ | 14.961039 gal |
| 3 ft³ | 22.441558 gal |
| 5 ft³ | 37.402597 gal |
| 10 ft³ | 74.805195 gal |
| 20 ft³ | 149.61039 gal |
| 50 ft³ | 374.02597 gal |
| 100 ft³ | 748.05195 gal |
| 1000 ft³ | 7480.5195 gal |
Cubic Foot (ft³)
Definition: The volume of a cube one foot on each side, equal to exactly 28.316846592 liters.
History: A natural geometric extension of the imperial foot, used in English-speaking countries since the standardization of the foot itself; its exact metric equivalent was fixed once the foot was tied to the meter by the 1959 international yard-and-pound agreement.
Current use: Common in the US for natural gas billing, HVAC airflow ratings, lumber and shipping volume, and refrigerator or freezer capacity.
Gallon (US) (gal)
Definition: A US customary unit equal to 4 US quarts, or exactly 3.785411784 liters.
History: Based on the old English wine gallon (231 cubic inches), which the US formally adopted as its liquid gallon standard in the 19th century. Britain instead adopted a larger imperial gallon (about 4.546 L) in 1824, so the US gallon and UK gallon have never been the same size — a common source of confusion when comparing fuel economy or recipe figures across countries.
Current use: The standard unit for fuel prices, milk jugs, and paint or motor oil containers throughout the United States.
Supported Units
| Unit | Symbol | In Liters |
|---|---|---|
| Milliliter | mL | 0.001 L |
| Liter | L | 1 L |
| Cubic Meter | m³ | 1000 L |
| Cubic Foot | ft³ | 28.316847 L |
| Cubic Inch | in³ | 0.016387064 L |
| Fluid Ounce (US) | fl oz | 0.02957353 L |
| Cup (US) | cup | 0.23658824 L |
| Pint (US) | pt | 0.47317647 L |
| Quart (US) | qt | 0.94635295 L |
| Gallon (US) | gal | 3.7854118 L |
About These Parameters
- Value
- The number you want to convert, expressed in the "From" unit. Accepts decimals.
- From Unit
- The unit your input value is currently measured in.
- To Unit
- The unit you want the result converted into. Use the swap button to flip From and To instantly.
How Volume Conversion Works
The Formula
Every unit here is defined by a fixed multiplier relative to the liter. To convert a value from one unit to another:
result = value × (factor of "From" unit ÷ factor of "To" unit)
For Cubic Foot → Gallon (US): multiply by 7.4805195. For example, 1 ft³ × 7.4805195 = 7.4805195 gal.
US Gallons vs. UK Imperial Gallons
This converter uses US customary volume units exclusively (fluid ounce, cup, pint, quart, gallon), which are not the same size as their UK imperial counterparts. A US gallon is exactly 3.785411784 liters, while a UK imperial gallon is about 4.546 liters — roughly 20% larger. Both systems trace back to old English measures, but the US kept the older wine-gallon standard after 1776 while Britain redefined its units in 1824. This mismatch is a common source of confusion when comparing fuel economy or recipe measurements between the US and UK.
Metric vs. US Customary Volume
The metric units on this page (milliliter, liter, cubic meter) all scale by powers of ten, so converting between them is just moving a decimal point. US customary units (fluid ounce, cup, pint, quart, gallon) use irregular multiples — 8 fluid ounces to a cup, 2 cups to a pint, 2 pints to a quart, 4 quarts to a gallon — inherited from centuries-old English liquid-measure tradition rather than a decimal system.
Volume in the Kitchen
Cups, pints, and quarts are primarily cooking and baking units in the United States — most other countries measure recipe ingredients by weight (grams) instead, which is more precise because ingredients like flour can pack differently depending on how they're scooped. When following a recipe written in cups or fluid ounces, converting to milliliters first can help if you're using a metric kitchen scale or measuring jug.
Example
1 ft³ equals 7.4805195 gal. For scale, that's about 28.32× a standard 1-liter water bottle (1 L, or 0.035314667 ft³).
Frequently Asked Questions
How many Gallons (US) are in 1 Cubic Foot?
1 Cubic Foot (ft³) equals exactly 7.4805195 Gallons (US) (gal).
Why is a US gallon smaller than a UK gallon?
The US kept the older English wine gallon (231 cubic inches, about 3.785 L) after independence, while the UK redefined its gallon in 1824 based on the volume of 10 pounds of water (about 4.546 L) — the two countries never reconciled the difference, so today "gallon" means two different volumes depending on where you are.
How many milliliters are in a US cup?
One US cup equals exactly 236.5882365 milliliters, though many recipes and kitchen tools round this to 240 mL for simplicity.
Is a cubic centimeter the same as a milliliter?
Yes — one cubic centimeter (cm³ or cc) is exactly equal to one milliliter by definition, which is why medical dosing is often labeled in either unit interchangeably.