What does karat mean?
A karat is a unit used to describe the purity of gold. The scale runs to 24 karats, with 24-karat gold representing pure gold; lower ratings indicate that the gold is alloyed with other metals. For example, 18-karat gold contains 18 parts gold and 6 parts other metals, making it 75 percent pure. The term is especially common in American English, where it is spelled “karat,” while British English generally uses “carat” for both gold purity and the weight of gemstones. Confusing the two spellings can therefore cause confusion: a karat concerns the fineness of gold, whereas a carat concerns weight. The unit is used in precise descriptions of jewellery and in regulations governing the quality of precious-metal products.
nounA unit used to express the purity of gold, with pure gold rated at 24 karats. Thus, 18-karat gold is three-quarters pure gold by weight.
- A unit used to indicate the purity of gold, with 24 karats representing pure gold.
"The bracelet is made from 18-karat gold."
"The jeweller explained that the setting was 18-karat gold."
"The regulation requires locally produced jewellery to be at least 22 karat."
The plural is used when referring to different gold-purity ratings.
"The guide compares 14-, 18-, and 24-karat gold."
Gold reaches maximum purity at 24 karats, so “24-karat gold” means pure gold rather than merely very high-quality gold.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does karat come from?
The word is an English variant spelling of “carat.” That form came through French from Italian carato and ultimately from Arabic qirāṭ, a term for the carob pod that was also associated with a small unit of weight; the Arabic word was borrowed from Greek kerátion, “carob pod.” The separate development of the spelling “karat” reflects its established use for expressing gold purity in American English.
Related word forms
How karat is actually used
“Karat” is chiefly an American spelling of “carat” in the sense of gold purity. It should not be confused with “carat,” the weight unit used for gemstones. In British usage, “carat” is normally used for both gold purity and gemstone weight.
Easily confused with karat
A karat measures the purity of gold, whereas a carat is a unit of weight used for gemstones and precious metals.