Tool
Karat, fineness and what the numbers mean
Convert karats to parts per thousand and back, and see how much actual gold sits inside each standard.
That is
14K · 583.3
Karat is a fraction of 24. Millesimal fineness is the same fraction written as parts per thousand — the number actually stamped on most modern jewellery.
Karat
14K
Fineness
583.3
parts per thousand
Gold by weight
58.33%
Other metals
41.67%
copper, silver, nickel, zinc
Every standard, side by side
| Stamp | Karat | % gold | Gold in 10 g |
|---|---|---|---|
| 9K · 375 | 9K | 37.5% | 3.75 g |
| 10K · 417 | 10K | 41.7% | 4.17 g |
| 12K · 500 | 12K | 50.0% | 5.00 g |
| 14K · 585 | 14K | 58.5% | 5.85 g |
| 15K · 625 | 15K | 62.5% | 6.25 g |
| 18K · 750 | 18K | 75.0% | 7.50 g |
| 20K · 833 | 20K | 83.3% | 8.33 g |
| 21K · 875 | 21K | 87.5% | 8.75 g |
| 22K · 916 | 22K | 91.6% | 9.16 g |
| 23K · 958 | 23K | 95.8% | 9.58 g |
| 24K · 999 | 24K | 99.9% | 9.99 g |
Where the stamp and the division disagree, the table follows the stamp. 14K works out at 583.3 and is stamped 583 in the US or 585 in Europe; 22K works out at 916.6 and is stamped 916 or 917. The difference is a fraction of a percent, and it is still the number on the metal.
Next
Weigh it, pick the karat, and see the value of the metal at the live gold price — then what a buyer is likely to hand over, which is a different number.
Sterling, coin, Britannia and fine silver at the live silver price — including why small silver items are often worth less than the trouble of selling them.
PT950, PT900 and PD950 at live prices. Both metals are denser than gold, which is why the weight surprises people.