Cubic Feet to Gallons: Complete Conversion Guide

Cubic Feet to Gallons: Complete Conversion Guide

1 cubic foot = 7.48052 US gallons. Multiply cubic feet by 7.48052 for US gallons. Multiply by 6.22884 for UK (imperial) gallons.

Conversion Formulas

• US gallons = cubic feet × 7.48052
• UK gallons = cubic feet × 6.22884
• Cubic feet = US gallons × 0.133681

Conversion Table

Cubic Feet	US Gallons	UK Gallons	Liters
1	7.48	6.23	28.32
5	37.40	31.14	141.58
10	74.81	62.29	283.17
25	187.01	155.72	707.92
50	374.03	311.44	1,415.84
100	748.05	622.88	2,831.68

Practical Examples

Swimming Pool

A pool measuring 30 ft × 15 ft × 5 ft average depth:

• Volume = 30 × 15 × 5 = 2,250 ft³
• Gallons = 2,250 × 7.48 = 16,830 US gallons

Aquarium

A 75-gallon aquarium = 75 × 0.133681 = 10.03 ft³.

External dimensions are typically 48” × 18” × 20” = 4 × 1.5 × 1.67 = 10.02 ft³ (glass thickness reduces internal volume slightly).

Water Heater

A 50-gallon water heater holds 50 × 0.133681 = 6.68 ft³ of water.

Hot Tub

A typical hot tub holds 300–500 gallons = 40–67 ft³ of water.

Why This Conversion Matters

• Pool maintenance: chemical dosing depends on gallons
• Water tanks: storage capacity planning
• Aquariums: sizing filters and heaters
• Plumbing: pipe flow calculations

Use our Cubic Feet Calculator unit converter to convert between cubic feet and gallons instantly.