Mass per volume density.
Pounds per Cubic foot to Pound per Cubic inches Converter — lb/ft3 to lb/in3
Convert Pound per Cubic foot (lb/ft3) to Pound per Cubic inch (lb/in3) using the exact conversion factor (1 pound per cubic foot = 0.0005787037 pound per cubic inch). See the formula, worked examples, conversion table, unit comparison, and common uses.
Pounds per Cubic foot to Pound per Cubic inches 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 / 27679.90471.
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 Pound per Cubic inches
Pound per Cubic foot and Pound per Cubic inch 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 Cubic inch is typically associated with united States.
Formula
pound per cubic inches = pounds per cubic foot × 0.000578703703704
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 cubic inch equals 27679.9047102 base units, so dividing one by the other gives the direct pound per cubic foot-to-pound per cubic inch factor of 0.000578703703704.
Simple example
1 lb/ft3 × 0.0005787037037 = 0.0005787037 lb/in3
1 pound per cubic foot = 0.0005787037 pound per cubic inches.
Real-world example
1,000 lb/ft3 × 0.0005787037037 = 0.5787037037 lb/in3
1,000 pounds per cubic foot = 0.5787037037 pound per cubic inches.
Conversion table
| Pound per Cubic foot (lb/ft3) | Pound per Cubic inch (lb/in3) |
|---|---|
| 0.1 lb/ft3 | 0.0000578704 lb/in3 |
| 1 lb/ft3 | 0.0005787037 lb/in3 |
| 10 lb/ft3 | 0.005787037 lb/in3 |
| 100 lb/ft3 | 0.0578703704 lb/in3 |
| 1,000 lb/ft3 | 0.5787037037 lb/in3 |
| 10,000 lb/ft3 | 5.787037037 lb/in3 |
Reverse conversion: Pound per Cubic inch to Pound per Cubic foot
0.0005787037 lb/in3 × 1728 = 0.9999999936 lb/ft3
0.0005787037 pound per cubic inches = 0.9999999936 pounds per cubic foot.
pounds per cubic foot = pound per cubic inches × 1728
For a page dedicated to this direction, see Pound per Cubic inch to Pound per Cubic foot.
Pound per Cubic foot vs. Pound per Cubic inch
| Aspect | Pound per Cubic foot | Pound per Cubic inch |
|---|---|---|
| Family | US customary density unit | US customary density unit |
| Typical use | US construction material density specs (concrete, soil, lumber, insulation) | Used in machining and materials engineering, particularly for describing the density of metals, where a smaller volume unit than the cubic foot gives a more convenient figure |
| Where it's used | United States (construction, engineering, materials specifications) | United States |
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 Cubic inch
Pound per Cubic inch (lb/in3) measures density. A US customary density unit suited to describing dense materials in a small volume. It is classified as a US customary density unit.
Where it's used: United States
Uses of the Pound per Cubic inch today
- Used in machining and materials engineering, particularly for describing the density of metals, where a smaller volume unit than the cubic foot gives a more convenient figure
Pound per Cubic foot — sources
- NIST Handbook 44 — General tables of units including US customary density measures.
Pound per Cubic inch — sources
- US materials-engineering reference tables — Pounds per cubic inch is a commonly tabulated density unit for metals in US machining and materials references.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many pound per cubic inches are in 1 pound per cubic foot?
1 pound per cubic foot equals 0.0005787037 pound per cubic inches, using the exact defined conversion factor rather than an estimate.
How do I convert pound per cubic foot to pound per cubic inch?
Multiply the pound per cubic foot value by 0.0005787037037. The converter above does this instantly to whatever precision you set.
How do I convert pound per cubic inch back to pound per cubic foot?
Use the reverse factor: 1 pound per cubic inch equals 1,728 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 cubic inch?
Pound per Cubic inch (lb/in3) measures density. A US customary density unit suited to describing dense materials in a small volume. It is classified as a US customary density unit.
Is the pound per cubic foot to pound per cubic inch conversion exact?
Yes. Both pound per cubic foot and pound per cubic inch are defined by fixed standards rather than physical artifacts, so the factor of 0.0005787037037 used above is exact to as many digits as you choose to display.
Where is the pound per cubic foot still used today?
United States (construction, engineering, materials specifications)
What's the difference between density and mass concentration?
Density is the mass of a pure substance or material per unit volume. Mass concentration is the mass of one component — like a dissolved solute — within a mixture's total volume. The two use the same kind of units but describe different physical situations.