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Carat to Ratti Converter

Convert a gemstone weight between carat, ratti and gram. The carat is fixed by international definition; the ratti is not, so the basis used here is stated on the page.

Conversions on this page use 1 ratti = 0.91 carat, and the international definition of 1 carat = 0.2 gram. The carat is a fixed standard; the ratti is not, and other values are in use in the trade — so check the basis before comparing this figure with one quoted elsewhere.

Carat to ratti and gram reference table
Carat (ct) Ratti Gram (g)
0.5 0.55 0.1
1 1.1 0.2
1.5 1.65 0.3
2 2.2 0.4
2.5 2.75 0.5
3 3.3 0.6
4 4.4 0.8
5 5.49 1.0
6 6.59 1.2
7 7.69 1.4
8 8.79 1.6
9 9.89 1.8
10 10.99 2.0
12 13.19 2.4

Good to know

Carat, ratti and gram

The carat is the international unit for gemstone weight and is fixed by definition at 0.2 gram. A stone described as 5 carat weighs exactly one gram, anywhere in the world.

The ratti is a traditional South Asian weight still widely used in Indian gem trade. Unlike the carat it is not standardised, and more than one value remains in circulation — which is why two jewellers can quote different ratti weights for the same stone without either being dishonest. Always check which basis a figure was calculated on before comparing it with another.

Every gemstone listed on this site states its weight on the product page, so you do not have to convert anything to know what you are buying.

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