Mass per volume density.
Pounds per Cubic foot to Pounds per Gallon Converter — lb/ft3 to lb/gal
Convert Pound per Cubic foot (lb/ft3) to Pound per Gallon (lb/gal) using the exact conversion factor (1 pound per cubic foot = 0.1336805556 pound per gallon). See the formula, worked examples, conversion table, unit comparison, and common uses.
Pounds per Cubic foot to Pounds per Gallon converter
Converter
Density Converter
Convert thousands of mass-per-volume density combinations for science, engineering, agriculture, and fluids.
Context values
Some unit families need one extra value for a physically accurate result.
Mass per volume density.
Result = input x 16.01846337 / 119.8264273.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Pounds per Cubic foot to Pounds per Gallon
Pound per Cubic foot and Pound per Gallon both measure density — mass per unit volume — a property used to identify materials, check manufacturing quality, and predict whether something floats or sinks. As a fixed reference point, water has a density of exactly 1000 kg/m³ (1 g/cm³, 1 g/mL) at its temperature of maximum density, which is why many density figures in science and engineering are quoted relative to water. Pound per Cubic foot is typically associated with united States (construction, engineering, materials specifications), while Pound per Gallon is typically associated with united States (paint, fuel, and industrial liquid density specifications).
Formula
pounds per gallon = pounds per cubic foot × 0.133680555556
This factor comes from each unit's defined relationship to the category's base unit: 1 pound per cubic foot equals 16.018463374 base units, and 1 pound per gallon equals 119.826427317 base units, so dividing one by the other gives the direct pound per cubic foot-to-pound per gallon factor of 0.133680555556.
Simple example
1 lb/ft3 × 0.1336805556 = 0.1336805556 lb/gal
1 pound per cubic foot = 0.1336805556 pounds per gallon.
Real-world example
1,000 lb/ft3 × 0.1336805556 = 133.6805556 lb/gal
1,000 pounds per cubic foot = 133.6805556 pounds per gallon.
Conversion table
| Pound per Cubic foot (lb/ft3) | Pound per Gallon (lb/gal) |
|---|---|
| 0.1 lb/ft3 | 0.0133680556 lb/gal |
| 1 lb/ft3 | 0.1336805556 lb/gal |
| 10 lb/ft3 | 1.336805556 lb/gal |
| 100 lb/ft3 | 13.36805556 lb/gal |
| 1,000 lb/ft3 | 133.6805556 lb/gal |
| 10,000 lb/ft3 | 1,336.805556 lb/gal |
Reverse conversion: Pound per Gallon to Pound per Cubic foot
0.1336805556 lb/gal × 7.480519481 = 1 lb/ft3
0.1336805556 pounds per gallon = 1 pounds per cubic foot.
pounds per cubic foot = pounds per gallon × 7.48051948052
For a page dedicated to this direction, see Pound per Gallon to Pound per Cubic foot.
Pound per Cubic foot vs. Pound per Gallon
| Aspect | Pound per Cubic foot | Pound per Gallon |
|---|---|---|
| Family | US customary density unit | US customary density unit |
| Typical use | US construction material density specs (concrete, soil, lumber, insulation) | US paint and coatings density specifications |
| Where it's used | United States (construction, engineering, materials specifications) | United States (paint, fuel, and industrial liquid density specifications) |
Understanding the Pound per Cubic foot
Pound per Cubic foot (lb/ft3) measures density. The US customary unit for expressing density, commonly used in construction and engineering material specifications. It is classified as a US customary density unit.
Where it's used: United States (construction, engineering, materials specifications)
Uses of the Pound per Cubic foot today
- US construction material density specs (concrete, soil, lumber, insulation)
- US engineering material property tables
- Bulk material handling and shipping weight estimates
Understanding the Pound per Gallon
Pound per Gallon (lb/gal) measures density. The US customary unit for liquid density, based on the US gallon (231 cubic inches). It is classified as a US customary density unit.
Where it's used: United States (paint, fuel, and industrial liquid density specifications)
lb/gal vs. lb/ft³. Both are US customary density units; they're related through the real, fixed relationship between the US gallon and the cubic foot (1 cubic foot ≈ 7.48 US gallons), not a round conversion factor.
Uses of the Pound per Gallon today
- US paint and coatings density specifications
- US fuel and petroleum liquid density specs
- Industrial liquid handling and shipping weight calculations
Pound per Cubic foot — sources
- NIST Handbook 44 — General tables of units including US customary density measures.
Pound per Gallon — sources
- NIST Handbook 44 — General tables of units including US customary density measures.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many pounds per gallon are in 1 pound per cubic foot?
1 pound per cubic foot equals 0.1336805556 pounds per gallon, using the exact defined conversion factor rather than an estimate.
How do I convert pound per cubic foot to pound per gallon?
Multiply the pound per cubic foot value by 0.1336805556. The converter above does this instantly to whatever precision you set.
How do I convert pound per gallon back to pound per cubic foot?
Use the reverse factor: 1 pound per gallon equals 7.480519481 pounds per cubic foot. You can also use the swap control in the converter above to flip the direction instantly.
What is a pound per cubic foot?
Pound per Cubic foot (lb/ft3) measures density. The US customary unit for expressing density, commonly used in construction and engineering material specifications. It is classified as a US customary density unit.
What is a pound per gallon?
Pound per Gallon (lb/gal) measures density. The US customary unit for liquid density, based on the US gallon (231 cubic inches). It is classified as a US customary density unit.
Is the pound per cubic foot to pound per gallon conversion exact?
Yes. Both pound per cubic foot and pound per gallon are defined by fixed standards rather than physical artifacts, so the factor of 0.1336805556 used above is exact to as many digits as you choose to display.
What is the difference between lb/gal vs. lb/ft³?
Both are US customary density units; they're related through the real, fixed relationship between the US gallon and the cubic foot (1 cubic foot ≈ 7.48 US gallons), not a round conversion factor.
Where is the pound per cubic foot still used today?
United States (construction, engineering, materials specifications)