Cubic Feet to U.S. Gallons Converter

One cubic foot contains 12³ = 1,728 cubic inches. One U.S. liquid gallon contains 231 cubic inches. Therefore:

$1\text{ ft}^3=\frac{1{,}728}{231}=7.480519480519\ldots\text{ US gal}$

Ten cubic feet equal about 74.8051948052 US gal, 283.16846592 L, and 299.220779221 quarts. The conversion uses the ratio rather than a truncated decimal. Negative or invalid numeric inputs and results too large to represent are rejected. Gallons are U.S. liquid gallons, not imperial gallons.

Related: the gallons to cubic feet converter for the reverse direction, the cubic feet calculator for computing ft³ from dimensions, and the gallons to liters calculator for the liter equivalents.

Distinguish geometric capacity from usable fill

For a tank estimate, calculate its internal volume in cubic feet before using this converter. The US-gallon result translates that geometry; it does not deduct fittings, sloping walls, or a fill reserve. Keep any usable-capacity adjustment separate so the conversion factor is not blamed for differences from a rated capacity.

Sources

• NIST, Guide for the Use of the International System of Units (SP 811) — SI units and accepted conversion guidance.
• NIST, Handbook 44, Appendix C — U.S. customary volume and length relationships used for dimensional arithmetic.