Gold purity: what 24K, 22K, 916 and 18K mean

Gold purity tells you what share of an item's weight is gold. It is useful when estimating the metal content of jewellery, bars or coins. The figure alone does not tell you the price a dealer will pay.

Common purity markings

24K means 24 parts gold out of 24. Our calculator uses 99.99% for its 24K option. 999 means 99.9% gold.

22K means 22 parts gold out of 24, or approximately 91.67%. 916 means 91.6% gold. These are close but not identical, so the calculator offers both.

18K means 18 parts gold out of 24, or 75%. 750 is another way to express that same 75% purity. 14K is approximately 58.33%, while 9K is 37.5%.

How to estimate pure gold weight

Multiply the item's weight by its purity fraction. For example, 10 grams of 916 gold contains an estimated 9.16 grams of gold. Ten grams of 18K or 750 gold contains 7.5 grams of gold.

How to estimate metal value

Multiply pure gold grams by a reference gold price per gram in your chosen currency. The gold value calculator does this using delayed supplier data and shows the market timestamp. The result excludes stones, workmanship, retail markups, dealer margins, taxes and other costs. Actual buying or selling offers can differ.

Which number should I enter?

Use the weight of the metal only if you know it. A jewellery item's total weight may include stones or non-gold components, which would make a simple estimate too high. If the mark says 916, choose 916 rather than rounding it to 22K: 916 represents 91.6% gold, while 22K is about 91.67%.

If you have a price quoted per troy ounce, divide it by 31.1034768 to estimate a price per gram before applying purity. The calculator handles that unit conversion for you. Currency selection changes the displayed reference value; exchange rates and dealer conversion rates can differ.