22K vs 18K Gold: Purity and Price Compared
22K is 22/24 gold by calculation; 18K is 18/24. Compare the fractions and quote inputs without treating karat as a durability test.
GoldNepal Content Team · Published
22K and 18K describe different gold proportions. On the 24-part karat scale, 22K is 22/24, or about 91.67% gold by calculation. 18K is 18/24, or 75%. For the same net weight of gold alloy, the 22K fraction contains more gold. These ratios explain the labels; they do not verify a particular item.
Compare 22K and 18K
| Rating | Calculation | Gold fraction | Common fineness example |
|---|---|---|---|
| 22K | 22 ÷ 24 | about 91.67% | 916 parts per thousand is commonly used as a 22K example |
| 18K | 18 ÷ 24 | 75% | 750 parts per thousand |
The 22K calculation is about 916.7 parts per thousand; a 916 fineness example may reflect the stated convention or rounding used in a market. Fineness and karat are related ways to describe gold content, but markings and accepted tolerances can vary. A number stamped or written on an item is not, by itself, an independent assay.
What the difference looks like by weight
For 10 grams of net gold alloy, 22K gives 10 x 22 ÷ 24 = about 9.17 grams of gold content by calculation. At 18K, 10 x 18 ÷ 24 = 7.5 grams. This example assumes the full 10 grams is gold-bearing alloy. It is not a test result, and it should not be applied to gross weight that includes stones or other materials.
Does 18K or 22K tell you which item is stronger?
Not on its own. Karat tells you the stated gold fraction, not the complete alloy recipe, construction, thickness, setting, or how a finished piece will wear. Alloy composition and workmanship both matter. Ask about the specific design instead of assuming that every 18K item is stronger or every 22K item is unsuitable for frequent wear.
Compare metal value on the same basis
A simple estimate uses the fine-gold reference rate for the same weight unit, multiplied by the karat fraction and the net gold-bearing weight. For example, the 22K factor is 22 ÷ 24; the 18K factor is 18 ÷ 24. Use like-for-like rate, weight, and purity inputs. This estimates a metal-value component; it is not a complete jewellery quote.
GoldNepal's karat calculator estimates metal value from the values entered. The weight converter can put two weights in the same unit. Neither tool tests an item or verifies the seller's figures.
Questions to ask before comparing two quotes
- What karat or fineness is stated for each item, and what documentation applies to it?
- Does the quoted weight refer to the gold-bearing alloy alone, or include stones and other parts?
- Are both estimates using the same fine-gold reference rate and weight unit?
- Which workmanship, stone, tax, or other line items are included in the final amount?
Keep those quote components separate from the purity calculation. Practices and quote formats differ, so compare the written details for the two specific items rather than assuming one universal billing method.
Sources and related guides
The World Gold Council guide to gold jewellery explains caratage and how alloy composition relates to colour. The LBMA guide to gold purity describes karat and fineness. For another specific comparison, read 18K vs 14K gold; for fineness-number context, see what 916, 750 and 585 state.