Convert Grams to Carats
1 gram is 5 ct. One gram is exactly 5 carats.
One gram is 5 carats. To convert grams to carats, multiply by 5; to go the other way, divide by 5 or multiply by 0.2. The factor is exact rather than rounded: it follows from NIST Handbook 44. One thousandth of a kilogram, and the unit nutrition labels use worldwide.
Factor checked against the defining standard · How we check
- Grams × 5
1 * 55 ct
1 gram in every weight unit
| Unit | Value | Exact factor |
|---|---|---|
| ounces | 0.03527396195 oz | × 0.0352739619496 |
| pounds | 0.002204622622 lb | × 0.00220462262185 |
| stone | 0.0001574730444 st | × 0.000157473044418 |
| US tons | 0.000001102311311 ton | × 0.00000110231131092 |
| micrograms | 1,000,000 mcg | × 1,000,000 |
| milligrams | 1,000 mg | × 1,000 |
| centigrams | 100 cg | × 100 |
| grams (as entered) | 1 g | — |
| kilograms | 0.001 kg | × 0.001 |
| slugs | 0.00006852176586 slug | × 0.0000685217658568 |
| tonnes | 0.000001 t | × 0.000001 |
| carats | 5 ct | × 5 |
| troy ounces | 0.03215074657 ozt | × 0.0321507465686 |
| grains | 15.43235835 gr | × 15.4323583529 |
| long tons | 0.0000009842065276 LT | × 0.000000984206527611 |
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 grams to carats? The converter and the working
- 1.Take the measurement in grams.
- 2.Multiply by 5 — that is how many carats fit in one gram.
- 3.To go back the other way, divide by 5, or multiply by 0.2.
Worked example: 25 grams to carats
- Formula
- g × 5 = ct
- Arithmetic
- 25 × 5 = 125 ct
- Answer
- 25 g = 125 ct
The factor is exact, so this figure is exact too — only the display is rounded.
Grams to carats conversion table
| Grams | Carats |
|---|---|
| 1 g | 5 ct |
| 2 g | 10 ct |
| 3 g | 15 ct |
| 4 g | 20 ct |
| 5 g | 25 ct |
| 6 g | 30 ct |
| 7 g | 35 ct |
| 8 g | 40 ct |
| 9 g | 45 ct |
| 10 g | 50 ct |
| 12 g | 60 ct |
| 15 g | 75 ct |
| 20 g | 100 ct |
| 25 g | 125 ct |
| 50 g | 250 ct |
| 100 g | 500 ct |
| 200 g | 1,000 ct |
| 300 g | 1,500 ct |
| 500 g | 2,500 ct |
| 1000 g | 5,000 ct |
| 2000 g | 10,000 ct |
| 5000 g | 25,000 ct |
| 10000 g | 50,000 ct |
A carat weighs the stone; a karat grades the gold
The carat is exactly 200 milligrams and measures the mass of a gemstone. The karat, spelled with a k in American use, measures the purity of gold in twenty-fourths — 18 karat is 18 parts gold in 24. They are different words for different quantities that sound identical out loud, and a jeweller quoting "22" means one or the other depending on what is in their hand.
NIST Handbook 44, Appendix C — general tables of units of measurement
What is a gram?
One thousandth of a kilogram, and the unit nutrition labels use worldwide.
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.
How many carats are in a gram?
One gram is 5 carats, exactly. Going the other way, one carat is 0.2 grams. 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 gram.
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Questions people actually ask
- How many carats are in a gram?
- 5. 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.
- How do I convert carats back to grams?
- Divide by 5, or multiply by 0.2 — they are the same operation.
Other weight conversions
Carats to grams — the same conversion the other way.