Mass per volume density.
Pound per Cubic inches to Pounds per Cubic foot Converter — lb/in3 to lb/ft3
Convert Pound per Cubic inch (lb/in3) to Pound per Cubic foot (lb/ft3) using the exact conversion factor (1 pound per cubic inch = 1,728 pound per cubic foot). See the formula, worked examples, conversion table, unit comparison, and common uses.
Pound per Cubic inches to Pounds per Cubic foot 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 27679.90471 / 16.01846337.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Pound per Cubic inches to Pounds per Cubic foot
Pound per Cubic inch and Pound per Cubic foot 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 inch is typically associated with united States, while Pound per Cubic foot is typically associated with united States (construction, engineering, materials specifications).
Formula
pounds per cubic foot = pound per cubic inches × 1728
This factor comes from each unit's defined relationship to the category's base unit: 1 pound per cubic inch equals 27679.9047102 base units, and 1 pound per cubic foot equals 16.018463374 base units, so dividing one by the other gives the direct pound per cubic inch-to-pound per cubic foot factor of 1728.
Simple example
1 lb/in3 × 1728 = 1,728 lb/ft3
1 pound per cubic inch = 1,728 pounds per cubic foot.
Real-world example
1,000 lb/in3 × 1728 = 1,728,000 lb/ft3
1,000 pound per cubic inches = 1,728,000 pounds per cubic foot.
Conversion table
| Pound per Cubic inch (lb/in3) | Pound per Cubic foot (lb/ft3) |
|---|---|
| 0.1 lb/in3 | 172.8 lb/ft3 |
| 1 lb/in3 | 1,728 lb/ft3 |
| 10 lb/in3 | 17,280 lb/ft3 |
| 100 lb/in3 | 172,800 lb/ft3 |
| 1,000 lb/in3 | 1,728,000 lb/ft3 |
| 10,000 lb/in3 | 17,280,000 lb/ft3 |
Reverse conversion: Pound per Cubic foot to Pound per Cubic inch
1 lb/ft3 × 0.0005787037037 = 0.0005787037 lb/in3
1 pound per cubic foot = 0.0005787037 pound per cubic inches.
pound per cubic inches = pounds per cubic foot × 0.000578703703704
For a page dedicated to this direction, see Pound per Cubic foot to Pound per Cubic inch.
Pound per Cubic inch vs. Pound per Cubic foot
| Aspect | Pound per Cubic inch | Pound per Cubic foot |
|---|---|---|
| Family | US customary density unit | US customary density unit |
| Typical use | 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 | US construction material density specs (concrete, soil, lumber, insulation) |
| Where it's used | United States | United States (construction, engineering, materials specifications) |
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
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
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.
Pound per Cubic foot — 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 cubic foot are in 1 pound per cubic inch?
1 pound per cubic inch equals 1,728 pounds per cubic foot, using the exact defined conversion factor rather than an estimate.
How do I convert pound per cubic inch to pound per cubic foot?
Multiply the pound per cubic inch value by 1728. The converter above does this instantly to whatever precision you set.
How do I convert pound per cubic foot back to pound per cubic inch?
Use the reverse factor: 1 pound per cubic foot equals 0.0005787037 pound per cubic inches. You can also use the swap control in the converter above to flip the direction instantly.
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.
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.
Is the pound per cubic inch to pound per cubic foot conversion exact?
Yes. Both pound per cubic inch and pound per cubic foot are defined by fixed standards rather than physical artifacts, so the factor of 1728 used above is exact to as many digits as you choose to display.
Where is the pound per cubic inch still used today?
United States
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.