Mass per volume density.
Stones per Cubic yard to Pounds per Cubic Millimeter Converter — st/yd3 to lb/mm3
Convert Stone per Cubic yard (st/yd3) to Pound per Cubic Millimeter (lb/mm3) using the exact conversion factor (1 stone per cubic yard = 1.831131e-8 pound per cubic millimeter). See the formula, worked examples, and conversion table.
Stones per Cubic yard to Pounds per Cubic Millimeter 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 8.305869898 / 4.5359237e+8.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Stones per Cubic yard to Pounds per Cubic Millimeter
Stone per Cubic yard and Pound per Cubic Millimeter 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
pounds per cubic millimeter = stones per cubic yard × 1.831131e-8
This factor comes from each unit's defined relationship to the category's base unit: 1 stone per cubic yard equals 8.30586989761 base units, and 1 pound per cubic millimeter equals 453592370 base units, so dividing one by the other gives the direct stone per cubic yard-to-pound per cubic millimeter factor of 1.831131e-8.
Simple example
1 st/yd3 × 1.831131e-8 = 1.831131e-8 lb/mm3
1 stone per cubic yard = 1.831131e-8 pounds per cubic millimeter.
Real-world example
1,000 st/yd3 × 1.831131e-8 = 0.0000183113 lb/mm3
1,000 stones per cubic yard = 0.0000183113 pounds per cubic millimeter.
Conversion table
| Stone per Cubic yard (st/yd3) | Pound per Cubic Millimeter (lb/mm3) |
|---|---|
| 0.1 st/yd3 | 1.831131e-9 lb/mm3 |
| 1 st/yd3 | 1.831131e-8 lb/mm3 |
| 10 st/yd3 | 1.831131e-7 lb/mm3 |
| 100 st/yd3 | 0.0000018311 lb/mm3 |
| 1,000 st/yd3 | 0.0000183113 lb/mm3 |
| 10,000 st/yd3 | 0.0001831131 lb/mm3 |
Reverse conversion: Pound per Cubic Millimeter to Stone per Cubic yard
1.831131e-8 lb/mm3 × 54611061.28 = 1.000000073 st/yd3
1.831131e-8 pounds per cubic millimeter = 1.000000073 stones per cubic yard.
stones per cubic yard = pounds per cubic millimeter × 54611061.2846
For a page dedicated to this direction, see Pound per Cubic Millimeter to Stone per Cubic yard.
Understanding the Stone per Cubic yard (st/yd3)
Mass per volume density.
Understanding the Pound per Cubic Millimeter (lb/mm3)
Mass per volume density.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many pounds per cubic millimeter are in 1 stone per cubic yard?
1 stone per cubic yard equals 1.831131e-8 pounds per cubic millimeter, using the exact defined conversion factor rather than an estimate.
How do I convert stone per cubic yard to pound per cubic millimeter?
Multiply the stone per cubic yard value by 1.831131e-8. The converter above does this instantly to whatever precision you set.
How do I convert pound per cubic millimeter back to stone per cubic yard?
Use the reverse factor: 1 pound per cubic millimeter equals 54,611,061.28 stones per cubic yard. You can also use the swap control in the converter above to flip the direction instantly.
What is a stone per cubic yard?
Stone per Cubic yard (st/yd3) is a unit of density.
What is a pound per cubic millimeter?
Pound per Cubic Millimeter (lb/mm3) is a unit of density.
Is the stone per cubic yard to pound per cubic millimeter conversion exact?
Yes. Both stone per cubic yard and pound per cubic millimeter are defined by fixed standards rather than physical artifacts, so the factor of 1.831131e-8 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.