Mass per volume density.
Carats per Tablespoon to Stones per Cup Converter — ct/tbsp to st/cup
Convert Carat per Tablespoon (ct/tbsp) to Stone per Cup (st/cup) using the exact conversion factor (1 carat per tablespoon = 0.0005039137 stone per cup). See the formula, worked examples, and conversion table.
Carats per Tablespoon to Stones per Cup 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 13.52560908 / 26841.11972.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Carats per Tablespoon to Stones per Cup
Carat per Tablespoon and Stone per Cup 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
stones per cup = carats per tablespoon × 0.000503913742137
This factor comes from each unit's defined relationship to the category's base unit: 1 carat per tablespoon equals 13.5256090807 base units, and 1 stone per cup equals 26841.119719 base units, so dividing one by the other gives the direct carat per tablespoon-to-stone per cup factor of 0.000503913742137.
Simple example
1 ct/tbsp × 0.0005039137421 = 0.0005039137 st/cup
1 carat per tablespoon = 0.0005039137 stones per cup.
Real-world example
1,000 ct/tbsp × 0.0005039137421 = 0.5039137421 st/cup
1,000 carats per tablespoon = 0.5039137421 stones per cup.
Conversion table
| Carat per Tablespoon (ct/tbsp) | Stone per Cup (st/cup) |
|---|---|
| 0.1 ct/tbsp | 0.0000503914 st/cup |
| 1 ct/tbsp | 0.0005039137 st/cup |
| 10 ct/tbsp | 0.0050391374 st/cup |
| 100 ct/tbsp | 0.0503913742 st/cup |
| 1,000 ct/tbsp | 0.5039137421 st/cup |
| 10,000 ct/tbsp | 5.039137421 st/cup |
Reverse conversion: Stone per Cup to Carat per Tablespoon
0.0005039137 st/cup × 1984.466619 = 0.9999999164 ct/tbsp
0.0005039137 stones per cup = 0.9999999164 carats per tablespoon.
carats per tablespoon = stones per cup × 1984.46661875
For a page dedicated to this direction, see Stone per Cup to Carat per Tablespoon.
Understanding the Carat per Tablespoon (ct/tbsp)
Mass per volume density.
Understanding the Stone per Cup (st/cup)
Mass per volume density.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many stones per cup are in 1 carat per tablespoon?
1 carat per tablespoon equals 0.0005039137 stones per cup, using the exact defined conversion factor rather than an estimate.
How do I convert carat per tablespoon to stone per cup?
Multiply the carat per tablespoon value by 0.0005039137421. The converter above does this instantly to whatever precision you set.
How do I convert stone per cup back to carat per tablespoon?
Use the reverse factor: 1 stone per cup equals 1,984.466619 carats per tablespoon. You can also use the swap control in the converter above to flip the direction instantly.
What is a carat per tablespoon?
Carat per Tablespoon (ct/tbsp) is a unit of density.
What is a stone per cup?
Stone per Cup (st/cup) is a unit of density.
Is the carat per tablespoon to stone per cup conversion exact?
Yes. Both carat per tablespoon and stone per cup are defined by fixed standards rather than physical artifacts, so the factor of 0.0005039137421 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.