Cubic Feet to Gallons Converter

A cubic foot holds about 7.48 U.S. gallons. Pool, tank and pond volumes measured in feet convert to gallons for buying water treatment chemicals.

How to use the Cubic Feet to Gallons Converter

1. Type the number of cubic feet into the Cubic feet field. Decimals such as 0.5 are fine.
2. Read the answer in US gallons – it updates as you type, with no button to press.
3. To convert the other way, type into US gallons and the cubic feet are recalculated.
4. Press Copy results to copy both values with the page title, or Copy link to share this exact conversion.

This page converts only ft³ ⇄ US gal. Need a different unit? Use the general volume converter, where you can choose any “from” and “to” unit.

How it works

Both units measure volume, so they are always in the same ratio: one cubic foot equals 7.4805195 US gallons. The calculator multiplies the number of cubic feet you type by 7.4805195 to give US gallons, and when you type into the US gallons field it divides by the same factor to give cubic feet. Because the ratio never changes, doubling the cubic feet always doubles the US gallons. Results are calculated at full precision and rounded only for display (up to eight decimal places, with very large or small values shown in scientific notation).

How to convert cubic feet to US gallons

1. Write down the value in cubic feet, for example 1 ft³.
2. Multiply by the conversion factor 7.4805195 (because 1 cubic foot = 7.4805195 US gal).
3. 1 × 7.4805195 = 7.4805195 US gal.
4. To go back from US gallons to cubic feet, divide by 7.4805195 – or multiply by 0.13368056.

ft³ to US gal conversion table

What is a cubic foot?

A cubic foot is a cube 1 ft on each side, about 28.32 litres or 7.48 U.S. gallons. Refrigerators, moving trucks, gas meters and lumber are measured in cubic feet in the U.S.

What is a US gallon?

The U.S. liquid gallon is exactly 231 cubic inches, about 3.785 litres. It is used for fuel, milk, water and paint in the United States.

Quick mental conversion

For a fast estimate, multiply cubic feet by about 7.5 to get US gallons; the error is about 0.3%. Use the calculator above when you need the exact figure.

Common mistakes to avoid

Mixing u.s. and uk gallons, pints and fluid ounces, assuming a cup is always 250 ml, and treating volume and weight as interchangeable for anything except water.