Convert Carats to Stone
1 carat is 0.00003149 st. One carat is exactly 0.0000314946088836 stone.
One carat is 3.1495 × 10^-5 stone. To convert carats to stone, multiply by 3.1495 × 10^-5; to go the other way, divide by 3.1495 × 10^-5 or multiply by 31751.466. The relation is exact but the figure is not: it is a rounding of a number that does not terminate, and it follows from NIST Handbook 44. Exactly 200 milligrams, fixed by international agreement in 1907 after centuries of local carats.
Factor checked against the defining standard · How we check
- Carats × 3.1495 × 10^-5
1 * 0.00003150 st
1 carat in every weight unit
| Unit | Value | Exact factor |
|---|---|---|
| ounces | 0.00705479239 oz | × 0.00705479238992 |
| pounds | 0.0004409245244 lb | × 0.00044092452437 |
| stone | 0.00003149460888 st | × 0.0000314946088836 |
| US tons | 0.0000002204622622 ton | × 0.000000220462262185 |
| micrograms | 200,000 mcg | × 200,000 |
| milligrams | 200 mg | × 200 |
| centigrams | 20 cg | × 20 |
| grams | 0.2 g | × 0.2 |
| kilograms | 0.0002 kg | × 0.0002 |
| slugs | 0.00001370435317 slug | × 0.0000137043531714 |
| tonnes | 0.0000002 t | × 0.0000002 |
| carats (as entered) | 1 ct | — |
| troy ounces | 0.006430149314 ozt | × 0.00643014931373 |
| grains | 3.086471671 gr | × 3.08647167059 |
| long tons | 0.0000001968413055 LT | × 0.000000196841305522 |
Factors are entered by hand from NIST Handbook 44 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert carats to stone? The converter and the working
- 1.Take the measurement in carats.
- 2.Multiply by 3.1495 × 10^-5 — that is how many stone fit in one carat.
- 3.To go back the other way, divide by 3.1495 × 10^-5, or multiply by 31751.466.
Worked example: 25 carats to stone
- Formula
- ct × 3.1495 × 10^-5 = st
- Arithmetic
- 25 × 3.1495 × 10^-5 = 0.0007874 st
- Answer
- 25 ct = 0.0007874 st
The factor is rounded for display; the figure above is computed from the full value.
Carats to stone conversion table
| Carats | Stone |
|---|---|
| 1 ct | 0.00003149 st |
| 2 ct | 0.00006299 st |
| 3 ct | 0.00009448 st |
| 4 ct | 0.000126 st |
| 5 ct | 0.0001575 st |
| 6 ct | 0.000189 st |
| 7 ct | 0.0002205 st |
| 8 ct | 0.000252 st |
| 9 ct | 0.0002835 st |
| 10 ct | 0.0003149 st |
| 12 ct | 0.0003779 st |
| 15 ct | 0.0004724 st |
| 20 ct | 0.0006299 st |
| 25 ct | 0.0007874 st |
| 50 ct | 0.001575 st |
| 100 ct | 0.003149 st |
| 200 ct | 0.01 st |
| 300 ct | 0.01 st |
| 500 ct | 0.02 st |
| 1000 ct | 0.03 st |
| 2000 ct | 0.06 st |
| 5000 ct | 0.16 st |
| 10000 ct | 0.31 st |
What is a carat?
Exactly 200 milligrams, fixed by international agreement in 1907 after centuries of local carats. It weighs a gemstone; the karat that grades gold is a different word for a different thing — purity in twenty-fourths.
What is a stone?
Fourteen pounds. Still the everyday unit of body weight in Britain and Ireland, and nowhere else.
How many stone are in a carat?
One carat is 3.1495 × 10^-5 stone. Going the other way, one stone is 31751.466 carats. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every weight unit here
The whole group — 15 units with their symbols and the size of each one in kilograms — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to a carat.
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- Chicago
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Questions people actually ask
- How many stone are in a carat?
- 3.1495 × 10^-5. Fourteen pounds. Still the everyday unit of body weight in Britain and Ireland, and nowhere else.
- How do I convert stone back to carats?
- Divide by 3.1495 × 10^-5, or multiply by 31751.466 — they are the same operation.
Other weight conversions
Stone to carats — the same conversion the other way.