Compare two gold karat grades side by side. Enter a weight and see how 24K, 22K, 18K, 14K, 10K or 9K gold differ in purity, fineness, fine-gold content and alloy content for the same amount of material.
See the actual gold-content difference for the same weight.
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Gold karat indicates the proportion of gold in an alloy using a 24-part scale. Comparing two karats therefore shows how much their gold content differs when the same weight of material is considered.
For example, 18K gold is 75% gold, while 14K gold is approximately 58.33% gold. If both are compared at the same weight, the 18K material contains more fine gold.
| Karat | Gold Purity | Fineness | Non-Gold Fraction |
|---|---|---|---|
| 24K | 100% | 1000 mathematically | 0% |
| 22K | 91.67% | 916.67 | 8.33% |
| 18K | 75% | 750 | 25% |
| 14K | 58.33% | 583.33 | 41.67% |
| 10K | 41.67% | 416.67 | 58.33% |
| 9K | 37.5% | 375 | 62.5% |
24K is the highest karat designation on the traditional 24-part scale, while 22K contains 22 parts gold out of 24. The mathematical difference is approximately 8.33 percentage points of gold content.
For 10 grams, the mathematical karat calculation gives 10 grams of fine gold for 24K and approximately 9.1667 grams for 22K.
Commercial fine-gold products may be specified with fineness values such as 999 or 999.9 rather than a literal 1000 marking.
22K contains approximately 91.67% gold, while 18K contains 75% gold. Therefore, the same weight of 22K material contains more fine gold.
For a 10-gram comparison, 22K contains approximately 9.1667 grams of fine gold, while 18K contains 7.5 grams.
18K gold is 75% gold, while 14K gold is approximately 58.33% gold. The difference is approximately 16.67 percentage points.
This means that for equal gross weight, an 18K alloy contains about 1.6667 grams more fine gold than a 14K alloy in a 10-gram comparison.
14K gold contains approximately 58.33% gold, while 10K gold contains approximately 41.67% gold.
For equal weight, the 14K material therefore contains a larger proportion of fine gold and a smaller proportion of other alloy metals.
10K gold contains approximately 41.67% gold, compared with 37.5% for 9K gold. The difference is approximately 4.17 percentage points.
At the same weight, the 10K alloy therefore contains more fine gold than 9K.
Karat becomes especially important when comparing the fine-gold content of equal weights. A higher karat means a larger fraction of the alloy is gold.
For example, compare 20 grams of 22K and 18K:
The comparison is based on the same gross weight. If the actual pieces have different weights, their fine-gold contents must be calculated separately.
Karat comparison tells you about gold content, but it does not by itself determine jewellery price.
Two pieces of identical weight and karat can have different prices because of workmanship, design, gemstones, brand, condition, market premiums, taxes and other costs.
The comparison assumes the entered weight represents the gold-alloy portion. If the scale weight includes gemstones, enamel or other non-gold materials, applying the karat percentage to the entire gross weight can overestimate fine-gold content.
For accurate metal-content calculations, use the known or estimated gold-alloy weight whenever possible.
This calculator compares stated karat grades mathematically. It does not test the composition of a physical item.
Hallmarks and purity stamps can provide useful information, but they do not make a mathematical calculator an authentication test. Professional testing or assay information may be needed when actual composition is uncertain.
It compares two karat grades by purity percentage, fineness, fine-gold content and alloy content for the same entered weight.
24K represents the highest karat grade on the traditional 24-part scale, while 22K contains 22 parts gold out of 24, or approximately 91.67% gold.
22K is approximately 91.67% gold while 18K is 75% gold. Therefore, the same weight of 22K contains more fine gold than the same weight of 18K.
The calculator determines the fine-gold weight for each karat using the same gross weight and subtracts the lower fine-gold result from the higher one.
No. Karat affects gold content, but jewellery price can also depend on weight, workmanship, gemstones, design, brand, taxes and other factors.
No. It compares stated karat grades mathematically and cannot authenticate a physical gold item.
Yes. Enter the weight and select two karat grades. The calculator shows the fine-gold content and difference for both grades.