Convert Grams to Carats
1 gram (g) equals 5 carats (ct).
Converting a list? Use the bulk gram to carat converter to paste a column from Excel.
How to Convert Gram to Carat
- 1 g = 5 ct
- 1 ct = 0.2 g
- Example: convert 15 g to ct: 15 g = 15 × 5 ct = 75 ct
Formula
ct = g × 5
Derivation from SI units:
- 1 g = 10⁻³ kg
- 1 ct = 200 mg (metric carat, exact)
- 1 g = 0.001 kg ÷ 0.0002 kg per ct = 5 ct
Both units are defined exactly, so the factor is exact. Gram definition: gram; Carat definition: carat.
Worked examples
- A 0.5 g stone is 2.5 ct.
0.5 g × 5 = 2.5 ct - 2 g is 10 ct.
2 g × 5 = 10 ct
Gram to Carat conversion table
| Grams (g) | Carats (ct) |
|---|---|
| 0.1 g | 0.5 ct |
| 0.5 g | 2.5 ct |
| 1 g | 5 ct |
| 2 g | 10 ct |
| 5 g | 25 ct |
| 10 g | 50 ct |
| 14 g | 70 ct |
| 20 g | 100 ct |
| 25 g | 125 ct |
| 28.35 g | 141.75 ct |
| 30 g | 150 ct |
| 50 g | 250 ct |
| 75 g | 375 ct |
| 100 g | 500 ct |
| 113 g | 565 ct |
| 125 g | 625 ct |
| 150 g | 750 ct |
| 200 g | 1000 ct |
| 250 g | 1250 ct |
| 300 g | 1500 ct |
| 454 g | 2270 ct |
| 500 g | 2500 ct |
| 750 g | 3750 ct |
| 1000 g | 5000 ct |
Where it's used
Gram masses are converted to carats to grade and price gemstones. Multiply by 5.
Gram to other weight and mass units
| Conversion | 1 g equals |
|---|---|
| gram to kilogram | 0.001 kg |
| gram to milligram | 1000 mg |
| gram to microgram | 1000000 µg |
| gram to metric ton | 0.000001 t |
| gram to pound | 0.002204622622 lb |
| gram to ounce | 0.03527396195 oz |
| gram to stone | 0.0001574730444 st |
| gram to short ton | 0.000001102311311 ton (US) |
| gram to long ton | 9.842065276 × 10⁻⁷ ton (UK) |
| gram to grain | 15.43235835 gr |
| gram to troy ounce | 0.03215074657 oz t |
| gram to carat | 5 ct |
Frequently asked questions
How many carats are in a gram?
Exactly 5.
How many carats are in 1 gram?
1 g = 5 ct.
How do I convert grams to carats?
Multiply the value in g by 5. For example, 15 g × 5 = 75 ct.
Is the g to ct conversion exact?
Yes. Both units are defined exactly, and 1 g is exactly 5 ct.
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "carat, metric".
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Grams to Carats. Retrieved October 17, 2026, from https://scientificconverters.com/mass/grams-to-carats/
IEEE
Scientific Converters, "Convert Grams to Carats," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/mass/grams-to-carats/