Gold karat chart: purity, fineness and 18k vs 24k gold
A gold karat chart shows how many parts out of 24 are pure gold: 24k is practically pure, while 18k is 75% gold and is often stamped 750. Below you’ll find karats from 9k to 24k, fineness numbers such as 999.9, 18k vs 24k gold, karat vs carat and how purity changes the price.
What is a gold karat, and how is it different from fineness?
A gold karat tells you how many parts out of 24 in a piece are pure gold. Purity is simply karat ÷ 24, so 18k gold is 18 ÷ 24 = 0.75, or 75% pure gold, and the rest of its weight is other metals.
Fineness measures the same thing in parts per 1000. To convert, divide the karat by 24 and multiply by 1000: 18k becomes 750. In practice, 24k usually means a purity of 99.9% or higher.
The global gold price is quoted for pure gold, so the karat tells you how much of that price is actually in your piece.
Gold karat chart: 9k to 24k
This chart lists the most common karats with their gold content and the fineness number usually stamped on the metal; typical uses vary by country.
Some fineness numbers are rounded: 22 ÷ 24 is about 91.67%, stamped 916, and the 585 standard for 14k is slightly above the exact 14 ÷ 24 (about 58.3%). 999 means 99.9% gold, and 999.9, sometimes called four nines, means 99.99%.
| Karat | Gold content | Fineness (stamp) | Typical use |
|---|---|---|---|
| 24k | 99.9% or more | 999 / 999.9 | Bars and bullion coins |
| 22k | 91.6% | 916 | Many bullion coins; jewellery in some regions |
| 21k | 87.5% | 875 | Jewellery common in the Arab world |
| 18k | 75% | 750 | Jewellery, very widely used |
| 14k | 58.5% | 585 | Jewellery with less gold, harder wearing |
| 9k | 37.5% | 375 | Lower-cost jewellery in some countries |
18k vs 24k gold: what’s the difference?
The main difference between 18k and 24k gold is how much pure gold they contain: one gram of 18k holds 0.75 g of pure gold, while one gram of 24k is almost entirely gold. So the gold in a gram of 18k is worth about three quarters of a gram of 24k.
Pure gold is soft; it scratches, bends and loses its shape easily. That is why jewellery is rarely made in 24k, which mostly comes as bars and bullion coins. Alloying gold with silver, copper, zinc or palladium makes it harder and more durable, and changes its colour.
Gold price per gram for 18k and 24k
- Gold content: 24k is 99.9% or more; 18k is 75%.
- Hardness: 24k is soft; 18k stands up better to everyday wear.
- Colour: 24k is a deep yellow; 18k can be yellow, white or rose, depending on the alloy.
Yellow, white and rose gold: where does the colour come from?
Yellow, white and rose gold are all gold alloys, and their colour comes from the metals mixed with the gold, not from the karat. An 18k ring can be yellow, white or rose and still contain 75% gold.
- Yellow gold: gold mixed with silver and copper, close to the colour of pure gold.
- Rose gold: a larger share of copper gives it a pinkish tone.
- White gold: gold mixed with white metals such as palladium, and often plated with a bright white metal, usually rhodium, which can wear off over time.
What does 750 mean on gold? Hallmarks and receipts
750 on gold means that 750 parts per 1000 of its weight are pure gold, which is 18k. Many pieces of jewellery and bars are stamped with a fineness number (such as 750, 585 or 999.9) or a karat mark (such as 18K); these marks are called hallmarks or purity stamps.
A stamp is a claim, not a guarantee. Hallmarking rules differ from country to country, and stamps can be faked. Before you buy:
- Buy from a well-known seller and get a receipt that lists weight, karat, making charges and tax separately.
- Check that the karat on the stamp matches the karat on the receipt.
- For cast gold or a piece with no stamp, ask for a purity test.
- Keep the receipt; it helps when you sell or in a dispute.
Karat vs carat: not the same thing
Karat measures the purity of gold, while a carat is a unit of weight for gemstones equal to 0.2 grams. A one-carat diamond weighs 0.2 g and says nothing about the karat of the ring it is set in.
Spelling differs by language and region. American English writes karat for gold and carat for gems, while British English often uses carat for both, as in 18ct gold. So read the context: next to gold, the number is purity; next to a stone, it is weight.
How to calculate the gold price by karat
The gold value of a piece is the price of one gram of pure gold × karat ÷ 24 × its weight in grams; with fineness, use fineness ÷ 1000 in place of karat ÷ 24. This is the value of the gold alone, without making charges, tax or the dealer’s margin.
Markets quote gold in different units and purities, so check which karat and unit (gram or troy ounce) each price refers to before comparing.
A made-up example: if one gram of pure gold cost 100 units of any currency, then:
From the ounce price to the 18k gram price
- One gram of 21k: 100 × 0.875 = about 87.5 units
- One gram of 18k: 100 × 0.75 = 75 units
- One gram of 14k (585 standard): 100 × 0.585 = about 58.5 units
- One troy ounce is 31.1034768 grams, so an ounce of pure gold has the gold content of about 41.47 g of 18k gold (31.1034768 ÷ 0.75 = 41.4713).
Making charges: why selling jewellery returns only the gold
Making charges are the cost of crafting jewellery, charged on top of the gold price, often with tax and the dealer’s margin added. When you sell, the buyer usually pays only for the gold content, by weight and karat; the making charges and tax don’t come back.
For example, a 10 g bracelet in 18k holds 7.5 g of pure gold, and its resale price is worked out from those 7.5 g, however high its making charges were. Bars and coins usually avoid jewellery-level making charges but may carry a premium; tokenized gold has no making charges but does have a conversion fee and a network fee.
Gold purity and Waletifi gold
Waletifi gold is tokenized gold backed by physical gold, where one full token represents one troy ounce. The token sits in your own wallet, and the app shows your gold balance in grams of 18k and in your own currency, a unit that is easy to compare with jewellery prices quoted for 18k.
The “Gold” screen shows a live price per gram and a chart over 1 day, 1 week, 1 month or 1 year, and the Waletifi site has a gold price page and gold piggy bank guides. Keep in mind that gold prices go up and down, and with tokenized gold you rely on the issuer that holds the backing gold.
