Gallons to Cubic Feet

Hydrological Metrology & NIST SP 811 Standards

In US Customary volumetric measurement, 1 cubic foot holds exactly 7.48051948 US liquid gallons.

Primary Volumetric Multipliers

• 1 Cubic Foot: 1,728 in^3 = 7.48052 US Gallons = 6.22884 UK Gallons = 28.3168 L

• 1 US Liquid Gallon: 231 in^3 = (1) / (7.48052) ft^3 ≈ 0.133681 ft^3 = 3.78541 L

• 1 CCF: = 100 ft^3 = 748.052 US Gallons = 2.8317 m^3

• Weight of 1 ft³ of Water: ≈ 62.43 lbs = 28.32 kg

Equations

• Cubic Feet = Gallons7.48051948

• Gallons = Cubic Feet × 7.48051948

How to Use This Calculator

Enter your Volume Value to Convert (e.g. 748.0), Gallon Standard — choose from US Liquid Gallon (1 ft³ = 7.48052 gal), UK Imperial Gallon (1 ft³ = 6.22884 gal), and Conversion Direction — choose from Gallons to Cubic Feet (gal → ft³ / divide by 7.481), Cubic Feet to Gallons (ft³ → gal / multiply by 7.481). Results update instantly as you type — adjust any value to compare scenarios.

The Formula

Formula Reference: Gallons to Cubic Feet

Input variables:

volumeValue — Volume Value to Convert

gallonTypeSelect — Gallon Standard

conversionDirectionSelect — Conversion Direction

Computed outputs:

convertedVolume — Converted Volume

equivalentCubicFeet — Volume in Cubic Feet (ft³)

equivalentGallons — Volume in Gallons (gal)

equivalentCcfBillingUnits — Water Utility Units (CCF / 100 ft³)

equivalentCubicMeters — Volume in Cubic Meters (m³)

Mathematical relationships extracted from calculation logic:

gal = val * galPerCft

cbm = cft * 0.028316846592

liters = cbm * 1000.0

lbsWater = cft * 62.42796; // 62.43 lbs/ft3 water

Standard: NIST Handbook 44 and BIPM SI unit definitions

Worked Example

A municipal residential water meter reading 1 CCF of monthly consumption equals exactly 100 cubic feet or 748 gallons of tap water delivered to the home.

Understanding Your Result

Unit conversion precision: round to the same number of significant figures as your original measurement. Converting 6 feet to meters gives 1.8288 m — but if your measurement was approximate (±1 inch), expressing more than 2 decimal places is false precision. For international trade and technical specifications, SI units (meters, kilograms, liters) are the standard. US customary units (feet, pounds, gallons) differ from Imperial UK units: 1 US gallon = 3.785 L vs. 1 UK gallon = 4.546 L.