Round Cut Diamond Size Chart (MM)

Wondering what a 1 carat round diamond looks link on a hand? Our round diamond size chart will help you convert millimeter (mm) size to carat size for round cut diamonds.

4 mm. 0.25 ct.
5.0 mm. 0.50 ct.
5.75 mm. 0.75 ct.
6.5 mm. 1.00 ct.
6.8 mm. 1.25 ct.
7.3 mm. 1.50 ct.
7.75 mm. 1.75 ct.
8 mm. 2.00 ct.
8.7 mm. 2.50 ct.
9.1 mm. 3.00 ct.
9.75 mm. 3.50 ct.
10.25 mm. 4.00 ct.
10.75 mm. 4.50 ct.
11 mm. 5.00 ct.

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Diamond Size FAQs

How is diamond size measured?

Is carat the only factor that affects the size appearance of a diamond?

Does the shape of a diamond influence how big it looks?

Can the setting make a diamond look bigger?

What's the difference between "carat weight" and "total carat weight"?

How does diamond size affect price?

Can two diamonds of the same carat weight appear different in size?

Is it better to get a slightly smaller diamond with higher quality or a bigger diamond with lower quality?

How can I accurately gauge the size of a diamond when shopping online?

Are there ethical considerations to keep in mind when choosing a diamond size?

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