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Cubic feet to gallons calculator

Enter any volume — cubic feet, gallons, litres, cubic metres, cubic yards — and get all the others instantly. Uses exact NIST conversion factors.

7.481US gal
Cubic yards (yd³)0.0370
US gallons (liquid)7.481
UK gallons (imperial)6.229
Litres (L)28.32
Cubic metres (m³)0.0283

1 ft³ = 7.4805 US gal = 6.2288 UK gal = 28.317 L. Exact factors from NIST SP 811.

Quick reference

Cubic feetUS gallonsUK gallonsLitres
1 ft³7.486.2328.32
5 ft³37.4031.14141.58
10 ft³74.8162.29283.17
27 ft³ (1 yd³)201.97168.18764.55
100 ft³748.05622.882,831.68

Common questions

How many gallons in a cubic foot?
1 cubic foot equals 7.4805 US gallons (liquid). Using the exact NIST definition: 1 ft³ = 28.316846592 litres; 1 US gallon = 3.785411784 litres; so 28.316846592 ÷ 3.785411784 = 7.480519480 US gallons per cubic foot.
How many gallons in 10 cubic feet?
10 cubic feet = 74.805 US gallons. Multiply cubic feet by 7.4805 to get US gallons, or enter 10 in the calculator above.
How many cubic feet in a gallon?
1 US gallon = 0.13368 cubic feet (1 ÷ 7.4805). 1 UK gallon = 0.16054 cubic feet. Use the calculator — pick 'US gal' or 'UK gal' as the from unit.
How many cubic feet in 55 gallons?
55 US gallons = 7.352 cubic feet. A standard 55-gallon drum is just under 7⅓ cubic feet. Multiply gallons by 0.13368 to convert.
How do I convert cubic feet to litres?
Multiply cubic feet by 28.317. So 1 ft³ = 28.317 L, 10 ft³ = 283.17 L. The exact factor is 28.316846592 L/ft³ (NIST SP 811).

Want the full explanation? Read the guide: How many gallons in a cubic foot? →

Last reviewed 2026-08.

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