Diamond Education

Diamond Carat Measurements

The diamond carat measurement is the universal standard unit of measurement used for the indication of diamond weights and other precious stones. Since the 19th century, the carat weight has been gauged against the metric system, with one carat equaling about 0.2 grams or otherwise, 0.007 ounces. Carat weight is often measured to three decimal points and then it’s rounded to the nearest hundredth.

Diamond carat weight varies, the exact weight is usually determined with the use of a diamond carat calculator. Each diamond carat is subdivided to 100 points. This allows a very precise diamond carat measurement to the hundredth decimal place.


Talking about the diamond carat size chart, some carat weights are considered to be the “magic sizes”. The magicsizes comprises of the half carat, three-quarter carat, and carat. While examining them visually, there’s only a little difference between a 0.99 carat diamond and one that weighs a full carat. But the price differences between the two is usually significant.

While the carat size rate measurement indicates the weight of a diamond, the length and width of its measurements denotes the actual physical size, or rather how big the diamond will appear when examined from an oval perspective. There is always the possibility of diamonds of the same carat weight varying in size. Take for example, a one-carat round diamond could measure up to 5.9 mm in diameter, while another one-carat round diamond could be 6.5 mm wide when measured. Broader diamonds with larger millimeter measurements create a much greater visual impact when viewed.