Mass per volume density.
Stones per Teaspoon to Carats per Cubic Millimeter Converter — st/tsp to ct/mm3
Convert Stone per Teaspoon (st/tsp) to Carat per Cubic Millimeter (ct/mm3) using the exact conversion factor (1 stone per teaspoon = 6.441868733 carat per cubic millimeter). See the formula, worked examples, and conversion table.
Stones per Teaspoon to Carats 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 1.28837375e+6 / 200000.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Stones per Teaspoon to Carats per Cubic Millimeter
Stone per Teaspoon and Carat 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
carats per cubic millimeter = stones per teaspoon × 6.44186873256
This factor comes from each unit's defined relationship to the category's base unit: 1 stone per teaspoon equals 1288373.74651 base units, and 1 carat per cubic millimeter equals 200000 base units, so dividing one by the other gives the direct stone per teaspoon-to-carat per cubic millimeter factor of 6.44186873256.
Simple example
1 st/tsp × 6.441868733 = 6.441868733 ct/mm3
1 stone per teaspoon = 6.441868733 carats per cubic millimeter.
Real-world example
1,000 st/tsp × 6.441868733 = 6,441.868733 ct/mm3
1,000 stones per teaspoon = 6,441.868733 carats per cubic millimeter.
Conversion table
| Stone per Teaspoon (st/tsp) | Carat per Cubic Millimeter (ct/mm3) |
|---|---|
| 0.1 st/tsp | 0.6441868733 ct/mm3 |
| 1 st/tsp | 6.441868733 ct/mm3 |
| 10 st/tsp | 64.41868733 ct/mm3 |
| 100 st/tsp | 644.1868733 ct/mm3 |
| 1,000 st/tsp | 6,441.868733 ct/mm3 |
| 10,000 st/tsp | 64,418.68733 ct/mm3 |
Reverse conversion: Carat per Cubic Millimeter to Stone per Teaspoon
6.441868733 ct/mm3 × 0.1552344578 = 1 st/tsp
6.441868733 carats per cubic millimeter = 1 stones per teaspoon.
stones per teaspoon = carats per cubic millimeter × 0.155234457813
For a page dedicated to this direction, see Carat per Cubic Millimeter to Stone per Teaspoon.
Understanding the Stone per Teaspoon (st/tsp)
Mass per volume density.
Understanding the Carat per Cubic Millimeter (ct/mm3)
Mass per volume density.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many carats per cubic millimeter are in 1 stone per teaspoon?
1 stone per teaspoon equals 6.441868733 carats per cubic millimeter, using the exact defined conversion factor rather than an estimate.
How do I convert stone per teaspoon to carat per cubic millimeter?
Multiply the stone per teaspoon value by 6.441868733. The converter above does this instantly to whatever precision you set.
How do I convert carat per cubic millimeter back to stone per teaspoon?
Use the reverse factor: 1 carat per cubic millimeter equals 0.1552344578 stones per teaspoon. You can also use the swap control in the converter above to flip the direction instantly.
What is a stone per teaspoon?
Stone per Teaspoon (st/tsp) is a unit of density.
What is a carat per cubic millimeter?
Carat per Cubic Millimeter (ct/mm3) is a unit of density.
Is the stone per teaspoon to carat per cubic millimeter conversion exact?
Yes. Both stone per teaspoon and carat per cubic millimeter are defined by fixed standards rather than physical artifacts, so the factor of 6.441868733 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.