Use our diamond size chart to understand the millimeter (mm) size of each diamond shape.

MM To Carat Conversion Chart: Round MOISSANITE Diamonds And Gemstones

Round MM Size	Round Carat Weight
4mm	0.25 ct.
4.5mm	0.36 ct.
5mm	0.5 ct.
5.5mm	0.66 ct.
5.75mm	0.75 ct.
6mm	0.84 ct.
6.5mm	1 ct.
7mm	1.3 ct.
7.5mm	1.67 ct.
8mm	2 ct.
8.5mm	2.11 ct.
9mm	2.75 ct.
9.5mm	3.35 ct.
10mm	3.87 ct.
10.5mm	4.41 ct.
11mm	4.91 ct.

 

Oval Cut Moissanite Diamond Size Chart (MM)

The Oval cut diamond varies in length-to-width ratios like the Emerald cut diamond. The chart below compiles average conversions for the millimeter measurements and carat weight of oval cut diamonds.

Oval MM Size	Oval Carat Weight
5x3 mm.	0.25 ct.
6x4 mm.	0.50 ct.
7x5 mm.	0.75 ct.
7.7x5.7 mm.	1.00 ct.
8x6 mm.	1.25 ct.
8.5x6.5 mm.	1.50 ct.
9x6.5 mm.	1.75 ct.
9x7 mm.	2.00 ct.
10x8 mm.	2.50 ct.
12x8 mm.	3.00 ct.
12x8.5 mm.	3.50 ct.
12.5x8.5 mm.	4.00 ct.
12.75x8.5 mm.	4.50 ct.
12x10 mm.	5.00 ct.

 

Princess Cut MOISSANITE Diamond Size Chart (MM)

Want to know how big a 2-carat princess cut diamond looks on a hand? Our princess-cut diamond size chart shows you the millimeter (mm) size for princess-cut diamonds.

Princess MM Size	Princess Carat Weight
3.25 mm.	0.25 ct.
4.5 mm.	0.50 ct.
5 mm.	0.75 ct.
5.5 mm.	1.00 ct.
6 mm.	1.25 ct.
6.5 mm.	1.50 ct.
6.75 mm.	1.75 ct.
7 mm.	2.00 ct.
7.5 mm.	2.50 ct.
8 mm.	3.00 ct.
8.5 mm.	3.50 ct.
8.75 mm.	4.00 ct.
9.25 mm.	4.50 ct.
9.5 mm.	5.00 ct.

Cushion Cut MOISSANITE Diamond Size Chart (MM)

Cushion-cut diamonds are one of the hardest shapes to predict size based on weight or millimeter measurements. Use our cushion diamond size chart to see how it would look on a hand.

Cushion MM Size	Cushion Carat Weight
3.25 mm.	0.25 ct.
4.9 mm.	0.50 ct.
5.25 mm.	0.75 ct.
5.5 mm.	1.00 ct.
6 mm.	1.25 ct.
6.5 mm.	1.50 ct.
6.75 mm.	1.75 ct.
7 mm.	2.00 ct.
7.5 mm.	2.50 ct.
8 mm.	3.00 ct.
8.5 mm.	3.50 ct.
9 mm.	4.00 ct.
9.3 mm.	4.50 ct.
9.5 mm.	5.00 ct.

Emerald Cut MOISSANITE Diamond Size Chart (MM)

Our Emerald cut diamond size chart includes a variety of common ratios and the standard conversions between millimeter measurements and carat weight for emerald diamonds.

Emerald MM Size	Emerald Carat Weight
4.30x3 mm.	0.25 ct.
6x4 mm.	0.50 ct.
6.5x4.5 mm.	0.75 ct.
7x5 mm.	1.00 ct.
7.3x5.3 mm.	1.25 ct.
7.5x5.5 mm.	1.50 ct.
8x6 mm.	1.75 ct.
8.5x6.5 mm.	2.00 ct.
9x7 mm.	2.50 ct.
9.3x7.5 mm.	3.00 ct.
9.75x7.7 mm.	3.50 ct.
10x8 mm.	4.00 ct.
10.5x8.5 mm.	4.50 ct.
11x9 mm.	5.00 ct.

Heart Cut MOISSANITE Diamond Size Chart (MM)

The ideal cut for a Heart shaped diamond is a square ratio of 1:1 for length and width. The chart below will help you convert the millimeter and carat weights for a heart cut diamond.

Heart MM Size	Heart Carat Weight
4 mm.	0.25 ct.
5 mm.	0.50 ct.
6 mm.	0.75 ct.
6.5 mm.	1.00 ct.
7 mm.	1.25 ct.
7.5 mm.	1.50 ct.
7.7 mm.	1.75 ct.
8 mm.	2.00 ct.
8.5 mm.	2.50 ct.
9 mm.	3.00 ct.
10 mm.	3.50 ct.
10.5 mm.	4.00 ct.
11 mm.	4.50 ct.
11.5 mm.	5.00 ct.

Pear Cut MOISSANITE Diamond Size Chart (MM)

Pear Cut diamonds vary widely in terms of cut proportions and resulting carat weights. The pear cut diamond size chart below will help you predict the expected size conversions for these diamonds.

Pear MM Size	Pear Carat Weight
5x3 mm.	0.25 ct.
6x4 mm.	0.50 ct.
7x5 mm.	0.75 ct.
7.7x5.7 mm.	1.00 ct.
8x6 mm.	1.25 ct.
8.5x6.5 mm.	1.50 ct.
10x6 mm.	1.75 ct.
9x7 mm.	2.00 ct.
10x8 mm.	2.50 ct.
12x8 mm.	3.00 ct.
12x9 mm.	3.50 ct.
14x8 mm.	4.00 ct.
14.5x9 mm.	4.50 ct.
15x9 mm.	5.00 ct.

Marquise Cut MOISSANITE Diamond Size Chart (MM)

Marquise diamonds vary widely in terms of measurement proportions and carat weight. Use the chart below to obtain the average conversion expectations for a marquise cut diamond.

Marquise MM Size	Marquise Carat Weight
6x3 mm.	0.25 ct.
8x4 mm.	0.50 ct.
9x4.5 mm.	0.75 ct.
10x5 mm.	1.00 ct.
11x5.5 mm.	1.25 ct.
12x6 mm.	1.50 ct.
12.5x6.25 mm.	1.75 ct.
13x6.5 mm.	2.00 ct.
14x7 mm.	2.50 ct.
15x7 mm.	3.00 ct.
15x8 mm.	3.50 ct.
16.5x8.25 mm.	4.00 ct.
16.75x8.5 mm.	4.50 ct.
17x8.5 mm.	5.00 ct.