Gold Purity — Karat, Fineness, Percentage Chart | OhMyUnit

Gold Purity

Gold purity is expressed as karats (24K = pure), fineness (out of 1000), or simple percentage. The chart matches all three side by side.

Karat	Fineness	% Gold	Description
24 K	999	99.9%	Pure gold (investment bullion)
22 K	916	91.6%	Common in Indian / Middle Eastern jewellery
21 K	875	87.5%	Popular in the Gulf region
20 K	833	83.3%	Less common, antique pieces
18 K	750	75.0%	Premium fine jewellery
14 K	585	58.5%	Most common in US fine jewellery
12 K	500	50.0%	Lower grade, less common
10 K	417	41.7%	Minimum legal karat in the US
9 K	375	37.5%	Common minimum in the UK
8 K	333	33.3%	Common minimum in Germany

Three notations

Karat (K): parts of pure gold in 24. 18K means 18/24 = 75% gold.
Fineness: parts of pure gold in 1000. 750 fineness = 75%.
Percentage: weight percentage of pure gold in the alloy.

Why pure gold is rarely used

24K gold is too soft for daily-wear jewellery — it scratches and bends easily. Mixing gold with copper, silver, or palladium produces an alloy that holds shape better. 18K and 14K are the most popular jewellery alloys; 22K is common in Indian and Middle Eastern wedding gold.

Hallmark stamps you may see

Modern jewellery is usually stamped with the fineness (e.g. 750, 585) or the karat number (18K, 14K). Older pieces may use a maker's mark plus an assay-office stamp.

FAQ

What about white gold? White gold has the same purity as yellow gold — the colour comes from the alloy metals (palladium, nickel) and an optional rhodium plating.

Is rose gold pure? Rose gold is gold + copper. 14K rose gold is still 14/24 = 58.3% gold; the rest is mostly copper.