Convert Cubic Foot to US Gallon (ft³gal (US))

The cubic foot is the American standard for HVAC capacity, natural gas billing, and refrigerator volume.

7.48052
1 ft³7.48052 gal (US)NIST · BIPM accuracy

Cubic Foot to US Gallon Conversion Table

10 common values
Cubic FootUS Gallon
1 ft³7.48052 gal (US)
2 ft³14.961039 gal (US)
5 ft³37.402597 gal (US)
10 ft³74.805195 gal (US)
20 ft³149.61039 gal (US)
50 ft³374.02597 gal (US)
100 ft³748.05195 gal (US)
200 ft³1,496.1039 gal (US)
500 ft³3,740.2597 gal (US)
1,000 ft³7,480.5195 gal (US)

How to Convert Cubic Foot to US Gallon Manually

Step by Step

Converting cubic feet to US gallons is straightforward: multiply by the conversion factor. Follow these three steps to do it by hand or in your head.

  1. 1
    Take your value in cubic feet
    Start with the number of cubic feet (ft³) you want to convert.
  2. 2
    Multiply by 7.48052
    The conversion factor from ft³ to gal (US) is 7.48052. Multiply your value by this number.
  3. 3
    Read the result in US gallons
    The result is your value in US gallons (gal (US)).
Practical Examples
1 ft³
equals
7.48052 gal (US)
5 ft³
equals
37.402597 gal (US)
10 ft³
equals
74.805195 gal (US)
25 ft³
equals
187.01299 gal (US)
100 ft³
equals
748.05195 gal (US)

Formula

Multiply the value in cubic feet by 7.48052. For the reverse direction, multiply by 0.133681.

Forwardgal (US) = ft³ × 7.48052
Reverseft³ = gal (US) × 0.133681
Example: 10 ft³ × 7.48052 = 74.805195 gal (US)

Tips

Use these in everyday conversions
  • 1 ft³ = 28.317 L = 0.0283 m³.
  • CFM to m³/h: multiply CFM by 1.699.
  • 1 m³ ≈ 35.3 ft³.

Common Mistakes

Avoid these
  • Confusing ft³ with ft² in US real-estate contexts.
  • Using 28 L instead of 28.32 L in precision HVAC calculations.
  • Mixing CCF (100 cubic feet) with CFM (cubic feet per minute) on utility bills.

About Cubic Foot and US Gallon

What is the Cubic Foot?

The cubic foot equals approximately 28.317 liters (or exactly 1,728 cubic inches) and is the American standard volume unit for HVAC capacity, natural-gas billing, refrigerator interior volume, and bulk material like concrete or mulch. American gas utilities measure delivered gas in 'CCF' (hundred cubic feet) or 'MCF' (thousand cubic feet), even when the customer thinks in terms of monthly bills. Refrigerators are advertised by their interior cubic-foot capacity (typical home unit: 18–25 ft³). Air-conditioning systems are rated in CFM (cubic feet per minute) airflow. Concrete is sometimes priced by the cubic yard (27 ft³), and mulch and topsoil are often sold by cubic foot bags. The cubic foot relates to the cubic yard (27 ft³ = 1 yd³), the cubic inch (1,728 in³ = 1 ft³), the cubic meter (1 ft³ ≈ 0.0283 m³), and the gallon (1 ft³ ≈ 7.481 US gal).

  • US air-conditioning and ventilation flow (CFM)
  • US natural gas consumption
  • Refrigerator and freezer capacity in the US
Real-world examples

A typical US fridge is 20 cu ft (566 L). US HVAC flow rated in CFM. US residential gas billed per 100 cu ft (CCF).

What is the US Gallon?

The US liquid gallon equals exactly 3.785411784 liters and is the standard volume unit for fuel, beverages, milk, and household liquids in the United States. Defined as 231 cubic inches, the US gallon descends from the English wine gallon of 1707, which Britain replaced with the larger imperial gallon in 1824 — a divergence that left the United States with a different gallon than the rest of the English-speaking world. American gas stations price gasoline by the gallon (typical fill-up: 12–15 gallons), milk is sold in half-gallons and gallons, and many beverages come in fluid-ounce subdivisions of the gallon. The US gallon relates to the liter (1 gal ≈ 3.785 L), the quart (4 qt = 1 gal), the pint (8 pt = 1 gal), the cup (16 cups = 1 gal), and the imperial gallon (1 imp gal ≈ 1.201 US gal — about 20% larger).

  • US fuel pricing and consumption
  • US paint, oil and cleaning-product packaging
  • US beverage containers (1-gallon jugs of milk)
Real-world examples

US car tank ≈ 15 gallons (57 L). 1 US gallon of milk is a common grocery size (3.79 L). US paint often sold by the gallon.

Learn About Both Units

🧪 Reference

What is the Cubic Foot?

Read the unit page →
🧪 Reference

What is the US Gallon?

Read the unit page →

Cubic Foot to US Gallon FAQ

5 questions
How many US gallons in a cubic foot?
One cubic foot equals 7.48052 US gallons.
How do I convert cubic feet to US gallons?
Multiply the cubic foot value by 7.48052 to get the equivalent in US gallons.
What is 100 cubic feet in US gallons?
100 cubic feet equals 748.05195 US gallons.
Is a cubic foot bigger than a us gallon?
Yes. 1 cubic foot equals 7.48052 US gallons, so one cubic foot is larger.
How to convert cubic feet to US gallons without a calculator?
Multiply by 7.48 for a quick estimate; use a calculator for precise results.

Related Volume Conversions

Full comparison →

Conversions From Other Categories