Mass per volume density.
Stones per Fluid ounce to Grains per Cubic Millimeter Converter — st/fl oz to gr/mm3
Convert Stone per Fluid ounce (st/fl oz) to Grain per Cubic Millimeter (gr/mm3) using the exact conversion factor (1 stone per fluid ounce = 3.313774225 grain per cubic millimeter). See the formula, worked examples, and conversion table.
Stones per Fluid ounce to Grains 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 214728.9578 / 64798.91.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Stones per Fluid ounce to Grains per Cubic Millimeter
Stone per Fluid ounce and Grain 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
grains per cubic millimeter = stones per fluid ounce × 3.31377422478
This factor comes from each unit's defined relationship to the category's base unit: 1 stone per fluid ounce equals 214728.957752 base units, and 1 grain per cubic millimeter equals 64798.91 base units, so dividing one by the other gives the direct stone per fluid ounce-to-grain per cubic millimeter factor of 3.31377422478.
Simple example
1 st/fl oz × 3.313774225 = 3.313774225 gr/mm3
1 stone per fluid ounce = 3.313774225 grains per cubic millimeter.
Real-world example
1,000 st/fl oz × 3.313774225 = 3,313.774225 gr/mm3
1,000 stones per fluid ounce = 3,313.774225 grains per cubic millimeter.
Conversion table
| Stone per Fluid ounce (st/fl oz) | Grain per Cubic Millimeter (gr/mm3) |
|---|---|
| 0.1 st/fl oz | 0.3313774225 gr/mm3 |
| 1 st/fl oz | 3.313774225 gr/mm3 |
| 10 st/fl oz | 33.13774225 gr/mm3 |
| 100 st/fl oz | 331.3774225 gr/mm3 |
| 1,000 st/fl oz | 3,313.774225 gr/mm3 |
| 10,000 st/fl oz | 33,137.74225 gr/mm3 |
Reverse conversion: Grain per Cubic Millimeter to Stone per Fluid ounce
3.313774225 gr/mm3 × 0.3017707098 = 1 st/fl oz
3.313774225 grains per cubic millimeter = 1 stones per fluid ounce.
stones per fluid ounce = grains per cubic millimeter × 0.301770709821
For a page dedicated to this direction, see Grain per Cubic Millimeter to Stone per Fluid ounce.
Understanding the Stone per Fluid ounce (st/fl oz)
Mass per volume density.
Understanding the Grain per Cubic Millimeter (gr/mm3)
Mass per volume density.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many grains per cubic millimeter are in 1 stone per fluid ounce?
1 stone per fluid ounce equals 3.313774225 grains per cubic millimeter, using the exact defined conversion factor rather than an estimate.
How do I convert stone per fluid ounce to grain per cubic millimeter?
Multiply the stone per fluid ounce value by 3.313774225. The converter above does this instantly to whatever precision you set.
How do I convert grain per cubic millimeter back to stone per fluid ounce?
Use the reverse factor: 1 grain per cubic millimeter equals 0.3017707098 stones per fluid ounce. You can also use the swap control in the converter above to flip the direction instantly.
What is a stone per fluid ounce?
Stone per Fluid ounce (st/fl oz) is a unit of density.
What is a grain per cubic millimeter?
Grain per Cubic Millimeter (gr/mm3) is a unit of density.
Is the stone per fluid ounce to grain per cubic millimeter conversion exact?
Yes. Both stone per fluid ounce and grain per cubic millimeter are defined by fixed standards rather than physical artifacts, so the factor of 3.313774225 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.