How to convert 8K gold to 21K
8K gold is 33.3% pure and 21K gold is 87.5% pure. To find the 21K weight with the same gold content, multiply the 8K weight by 0.333 and divide by 0.875. One gram of 8K equals 0.3806 grams of 21K.
Example
10 g of 8K gold contains 3.33 g of pure gold, the same as 3.8057 g of 21K. Today 10 g of 8K is worth $443.28.
When you need this conversion
- Exchanging old jewelry for new pieces in a different karat.
- Comparing prices quoted per gram of 22k with prices quoted for 18k or 24k.
- Planning how much of a karat a jeweler needs to remake an item.
Note that remaking jewelry involves melting losses and labor, so a jeweler's exchange rate is usually below this pure-gold equivalent. See methodology.