How many carats is a 20 mm diamond?
By HeyGema™ · Updated
In short
A 20 mm round diamond weighs about 29.81 carat (5.96 grams). A 20 mm princess cut weighs about 48.08 carat, and an oval that is 20 mm long about 15.7 carat.
- 29.81 ctround diamond, 20 mm
- 5.96 gweight
- 0.79 in20 mm in inches
Carat to mm calculator
About 29.81 carat
An estimate for a well-cut stone. A deep or shallow cut faces up smaller or bigger.
20 mm diamond weight by shape
The weight of a well-cut diamond measuring 20 mm. For round and square shapes the number is the diameter or the side. For longer shapes it is the long side, with the width following the usual ratio.
- Round
- Size: 20 mm
- Weight: 29.81 ct
- Oval
- Size: 20 mm x 13.8 mm
- Weight: 15.7 ct
- Cushion
- Size: 20 mm x 20.0 mm
- Weight: 45.55 ct
- Princess
- Size: 20 mm x 20.0 mm
- Weight: 48.08 ct
- Emerald cut
- Size: 20 mm x 14.3 mm
- Weight: 23.32 ct
- Asscher
- Size: 20 mm x 20.0 mm
- Weight: 48.08 ct
- Radiant
- Size: 20 mm x 15.4 mm
- Weight: 29.13 ct
- Pear
- Size: 20 mm x 12.9 mm
- Weight: 12.97 ct
- Marquise
- Size: 20 mm x 10.0 mm
- Weight: 7.11 ct
- Heart
- Size: 20 mm x 20.0 mm
- Weight: 29.13 ct
- Trillion
- Size: 20 mm x 20.0 mm
- Weight: 23.32 ct
- Baguette
- Size: 20 mm x 10.0 mm
- Weight: 15.63 ct
20 mm stones in other gems
A round stone of the same size weighs differently in each gem, because gems differ in density.
- Diamond
- Weight of a round stone: 29.81 ct
- Moissanite
- Weight of a round stone: 27.27 ct
- Sapphire
- Weight of a round stone: 33.88 ct
- Ruby
- Weight of a round stone: 33.88 ct
- Emerald
- Weight of a round stone: 23.04 ct
- Aquamarine
- Weight of a round stone: 22.87 ct
- Topaz
- Weight of a round stone: 29.9 ct
- Amethyst
- Weight of a round stone: 22.44 ct
- Spinel
- Weight of a round stone: 30.49 ct
- Tanzanite
- Weight of a round stone: 28.37 ct
- Morganite
- Weight of a round stone: 23.72 ct
20 mm diamond studs
A pair of 20 mm round diamond studs has a total carat weight of about 59.63 carat, 29.81 carat for each stone. See the diamond stud earring size chart.
Nearby sizes
Questions
About 29.81 carat for a well-cut round diamond.
A 20 mm princess cut, measured along one side, weighs about 48.08 carat.
A 20 mm round moissanite is labeled 29.81 carat (diamond equivalent weight) and weighs about 27.27 carat. See the moissanite size chart.
20 mm is 0.79 inches.