Gold Karat Calculator
Example: 10 g of 21K gold (87.5% pure) holds 8.75 g of pure gold. At an entered price of 300 per gram of pure gold, that is worth 2,625. The price is an example, not a market quote.
How to use
- Enter the weight and choose grams, troy ounces or tola.
- Pick the karat, or choose custom and type the fineness stamped on the piece, for example 925.
- Enter today's price per gram of pure gold (24K) from your dealer or a source you trust. The calculator does not fetch prices.
- Read the value, the pure gold content and the price per gram at that karat.
How it works
Value = weight in grams × purity × price per gram of pure gold.
Purity is the fineness divided by 1000: 24K = 999 (99.9%), 22K = 916 (91.6%), 21K = 875 (87.5%), 18K = 750 (75%), 14K = 585 (58.5%), 10K = 417 (41.7%), 9K = 375 (37.5%).
1 troy ounce = 31.1034768 g and 1 tola = 11.6638038 g.
Karat and purity
| Karat | Fineness | Purity | Pure gold in 10 g |
|---|---|---|---|
| 24K | 999 | 99.9% | 9.99 g |
| 22K | 916 | 91.6% | 9.16 g |
| 21K | 875 | 87.5% | 8.75 g |
| 18K | 750 | 75% | 7.5 g |
| 14K | 585 | 58.5% | 5.85 g |
| 10K | 417 | 41.7% | 4.17 g |
| 9K | 375 | 37.5% | 3.75 g |
Why a shop price can differ
The result is the value of the gold content at the price you enter. Jewellery shops usually add making charges and taxes when you buy, and pay less than the gold price when they buy back. Dealers also quote prices per karat that differ slightly from a straight purity calculation.
This tool is for estimates and is not investment advice.
FAQ
Is 24K gold 100% pure?
In trade, 24K gold is stamped 999, which is 99.9% pure. This calculator uses 99.9% for 24K.
Which price should I enter?
The price per gram of pure gold (24K). The calculator multiplies it by the purity of your piece. If you only know the price of another karat, divide it by that karat's purity first.
Why is 22K shown as 91.6% and not 91.67%?
The common stamp for 22K is 916. The exact fraction 22/24 is 91.67%, but the stamped fineness is what the market uses.
Does the calculator include making charges or tax?
No. It values the gold content only. Add the dealer's charges and taxes separately.