Mass per volume density.
Stones per Cubic Millimeter to Pound per Cubic inches Converter — st/mm3 to lb/in3
Convert Stone per Cubic Millimeter (st/mm3) to Pound per Cubic inch (lb/in3) using the exact conversion factor (1 stone per cubic millimeter = 229,418.896 pound per cubic inch). See the formula, worked examples, conversion table, and common uses.
Stones per Cubic Millimeter 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 6.35029318e+9 / 27679.90471.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Stones per Cubic Millimeter to Pound per Cubic inches
Stone per Cubic Millimeter 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. Both are mass per volume density units.
Formula
pound per cubic inches = stones per cubic millimeter × 229418.896
This factor comes from each unit's defined relationship to the category's base unit: 1 stone per cubic millimeter equals 6350293180 base units, and 1 pound per cubic inch equals 27679.9047102 base units, so dividing one by the other gives the direct stone per cubic millimeter-to-pound per cubic inch factor of 229418.896.
Simple example
1 st/mm3 × 229418.896 = 229,418.896 lb/in3
1 stone per cubic millimeter = 229,418.896 pound per cubic inches.
Real-world example
1,000 st/mm3 × 229418.896 = 229,418,896 lb/in3
1,000 stones per cubic millimeter = 229,418,896 pound per cubic inches.
Conversion table
| Stone per Cubic Millimeter (st/mm3) | Pound per Cubic inch (lb/in3) |
|---|---|
| 0.1 st/mm3 | 22,941.8896 lb/in3 |
| 1 st/mm3 | 229,418.896 lb/in3 |
| 10 st/mm3 | 2,294,188.96 lb/in3 |
| 100 st/mm3 | 22,941,889.6 lb/in3 |
| 1,000 st/mm3 | 229,418,896 lb/in3 |
| 10,000 st/mm3 | 2,294,188,960 lb/in3 |
Reverse conversion: Pound per Cubic inch to Stone per Cubic Millimeter
1 lb/in3 × 0.000004358838864 = 0.0000043588 st/mm3
1 pound per cubic inch = 0.0000043588 stones per cubic millimeter.
stones per cubic millimeter = pound per cubic inches × 0.00000435883886391
For a page dedicated to this direction, see Pound per Cubic inch to Stone per Cubic Millimeter.
Understanding the Stone per Cubic Millimeter (st/mm3)
Mass per volume density.
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 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 stone per cubic millimeter?
1 stone per cubic millimeter equals 229,418.896 pound per cubic inches, using the exact defined conversion factor rather than an estimate.
How do I convert stone per cubic millimeter to pound per cubic inch?
Multiply the stone per cubic millimeter value by 229418.896. The converter above does this instantly to whatever precision you set.
How do I convert pound per cubic inch back to stone per cubic millimeter?
Use the reverse factor: 1 pound per cubic inch equals 0.0000043588 stones per cubic millimeter. You can also use the swap control in the converter above to flip the direction instantly.
What is a stone per cubic millimeter?
Stone per Cubic Millimeter (st/mm3) is a unit of density.
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 stone per cubic millimeter to pound per cubic inch conversion exact?
Yes. Both stone per cubic millimeter and pound per cubic inch are defined by fixed standards rather than physical artifacts, so the factor of 229418.896 used above is exact to as many digits as you choose to display.
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.