Match the Seville Ring to the Florence Ring for a perfect bridal set
mm to Carat Stone Size Chart
Round-cut

Timeless and classic, round diamonds offer the highest brilliance reflected by 58 precise facets. Its round shape symbolizes eternity and is the most popular and expensive diamond cut that is perfect for engagement and wedding rings. Our stone sizing chart below shows the standard sizes and matching carat weights for round-cut diamonds to help you find your perfect fit. 

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Printable Size Chart



Round Diamond Average Carat by Millimeter Conversions

Classic and brilliant, round cut stones are a popular choice for engagement rings in both traditional and modern settings. | Shop Kobelli Round Centered Jewelry.


Approx. Millimeter
Approx. Carat Weight
4
0.25
5
0.5
6.5
1
7
1.25
7.5
1.5
8
2
9
2.5
9.5
3
9.7
3.5
10
4
10.5
4.5
11
5

Round

Cushion

Oval

Marquise

Pear

Emerald

Radiant

Asscher

FAQ

How much does a listed carat weight vary by?

All diamond weights may vary by 5% unless stated otherwise. One-of-a-kind products will showcase the exact weight of all stones.

Do moissanites weigh the same as diamonds?

Not quite - while the moissanite gemstone is technically slightly lighter in weight due to a lower density, the stones are most commonly marketed by their Diamond Equivalent Weight (DEW) in accordance to the millimeter size of the stone rather than the weight of the stone itself.

All of Kobelli's moissanite products will be listed with the Diamond Equivalent Weights (DEW). This allows for an identical dimensional look if you are to upgrade your existing moissanite center stone for a diamond.

What about other gemstones?

Gemstones, aside from moissanites, will be listed in accordance to either their millimeter size or their carat weight. Every stone type carries its own unique traits for density and depth.