MM to Carat Weight Conversion

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Nexus Diamond™ Alternatives

You’ve decided that you want to go with a lab created diamond simulant. Now it’s time to pick the shape, millimeter size, carat weight and more. Click on the the cut to view its mm to carat conversion chart.

Round

Princess

Asscher

Cushion

Oval

Radiant

Emerald

Pear

Heart

Marquise

Triangle

Trillion

Baguette

Tapered Baguette

Round Cut

Shop Round Cut

MM Size	Carat Weight
0.8	0.0025
1	0.005
1.12	0.0075
1.15	0.0067
1.25	0.01
1.3	0.01
1.5	0.015
1.75	0.02
1.8	0.025
2	0.03
2.25	0.04
2.5	0.06
2.75	0.08
3	0.11
3.25	0.14
3.5	0.17
3.75	0.21
4	0.25
4.25	0.28
4.5	0.36
4.75	0.44
5	0.46
5.25	0.56
5.5	0.66
5.75	0.76
6	0.84
6.25	0.93
6.5	1.03
6.75	1.24

MM Size	Carat Weight
7	1.28
7.25	1.49
7.5	1.67
7.75	1.75
8	2.04
8.25	2.11
8.5	2.43
8.75	2.55
9	2.75
9.25	3.05
9.5	3.35
9.75	3.61
10	3.87
10.25	4.16
10.5	4.41
10.75	4.57
11	4.91
11.25	5.49
11.5	5.85
12	6.84
12.25	7.26
12.5	7.36
12.75	7.52
13	8.51
13.5	9.53
14	10.49
15	12.89
16	16.06

Princess / Square Cut

Shop Princess Cut

MM Size	Carat Weight
1.5	0.015
1.75	0.03
2	0.06
2.25	0.08
2.5	0.1
2.75	0.13
3	0.18
3.25	0.26
3.5	0.29
3.75	0.31
4	0.39
4.25	0.44
4.5	0.56
4.75	0.64
5	0.71
5.25	0.75
5.5	0.99
5.75	1.11
6	1.24
6.25	1.39

MM Size	Carat Weight
6.5	1.59
6.75	1.75
7	1.96
7.25	2.01
7.5	2.4
7.75	2.74
8	3.01
8.25	3.24
8.5	3.67
8.75	4.1
9	4.12
9.5	5.09
9.75	5.36
10	5.62
10.25	5.76
10.5	5.99
11	7.44
11.5	9.44
12	9.52

Asscher Cut

Shop Asscher Cut

MM Size	Carat Weight
4	0.39
4.5	0.56
5	0.71
5.5	0.99
6	1.24
6.5	1.59
7	1.96
7.5	2.4

MM Size	Carat Weight
8	3.01
8.5	3.67
9	4.12
9.5	5.09
10	5.62
11	7.44
12	9.52
13	12.66

Marquise Cut

Shop Marquise Cut

MM Size	Carat Weight
3 x 1.5	0.025
3.5 x 1.75	0.065
3.5 x 2	0.07
3.75 x 1.75	0.11
4 x 2	0.1
4.25 x 2.25	0.12
5 x 2.5	0.14
5 x 3	0.2
5.5 x 2.75	0.16
5.5 x 3	0.18
6 x 3	0.25
6.5 x 3	0.23
7 x 3	0.3
7 x 3.5	.35
7 x 4	3.4
7.5 x 3.5	0.33
8 x 4	0.47
9 x 4.5	0.71

MM Size	Carat Weight
9 x 5	0.76
9.5 x 5	0.85
10 x 5	0.95
11 x 5.5	1.25
11.5 x 6	1.33
12 x 6	1.62
12 x 6.5	1.71
13 x 6.5	2.11
14 x 7	2.48
15 x 7.5	3.09
14 x 8	3
15 x 7	3.12
15 x 8	3.44
16 x 8	3.86
17 x 8.5	4.88
17.5 x 10	5.5
20 x 8	7.08
20 x 10	7.94
20 x 11	9.5

Radiant Cut

Shop Radiant Cut

MM Size	Carat Weight
4.5 x 3.5	0.34
5 x 3	0.31
6 x 3	0.41
6 x 4	.60
6.5 x 4.5	0.83
7 x 5	1.14
7.25 x 5.25	1.24
7.5 x 5.5	1.47
8 x 6	1.74
8.5 x 6.5	2.25
9 x 7	2.62
9.5 x 7.5	3.18
10 x 7	3.31

MM Size	Carat Weight
10 x 8	3.49
11 x 9	5.05
11.5 x 10	6.45
12 x 9	6.06
12 x 10	6.79
13 x 9	6.54
13 x 11	9.33
13.5 x 11.5	10.19
14 x 10	8.47
14 x 12	12.14
15 x 11	11.48
16 x 12	14.22

Cushion Cut

Shop Cushion Cut

MM Size	Carat Weight
4	0.25
4.5	0.36
5	0.46
5.25	0.56
5.5	0.66
5.75	0.76
6	0.84
6.25	0.93
6.5	1.03
6.75	1.24
7	1.28
7.5	1.67

MM Size	Carat Weight
8	2.04
8.5	2.43
9	2.75
9.5	3.35
10	3.87
10.5	4.41
11	4.91
11.5	5.85
12	6.84
13	8.51
14	10.49
15	12.89

Pear Cut

Shop Pear Cut

MM Size	Carat Weight
3 x 2	0.13
4 x 2.5	0.18
4 x 3	0.21
5 x 3	0.25
5 x 4	0.35
6 x 4	0.39
6.5 x 4.5	0.57
7 x 5	0.71
8 x 5	0.81
8.5 x 5.5	1.08
8 x 6	1.25
9 x 6	1.33
9 x 7	1.75
10 x 6	1.71
10 x 7	1.8
10 x 8	2.46
11 x 7.50	2.61
11 x 8	3
12 x 7	3.12

MM Size	Carat Weight
12 x 8	3
12 x 9	3.44
13 x 8	2.98
14 x 8	3.47
13 x 9	4.11
14 x 9	4.25
15 x 9	5.06
14 x 10	5.41
13 x 11	5.65
15 x 10	5.75
15 x 11	7.36
16 x 9	5.86
16 x 10	6.27
16 x 12	8.99
17 x 10	6.46
18 x 11	8.14
18 x 12	9.35
18 x 13	10.21

Oval Cut

Shop Oval Cut

MM Size	Carat Weight
4.5 x 3.5	0.21
5 x 3	0.21
5 x 4	0.35
5.5 x 3.5	0.33
6 x 4	0.43
6.5 x 4.5	0.65
6 x 5	0.61
7 x 5	0.76
7.5 x 5.5	0.98
8 x 6	1.21
8.5 x 6.5	1.46
9 x 6	1.41
9 x 7	1.86

MM Size	Carat Weight
10 x 8	2.54
10.5 x 8.5	2.88
11 x 9	3.85
12 x 8	2.99
12 x 10	5.05
14 x 10	5.81
13 x 11	6.05
14 x 12	8.21
15 x 12	8.76
16 x 12	9.32
16 x 14	11.88
18 x 13	12.86
20 x 15	14.96

Heart Cut

Shop Heart Cut

MM Size	Carat Weight
3.5	0.18
4	0.25
4.25	0.28
4.5	0.34
4.75	0.38
5	0.44
5.5	0.61
6	0.74
6.25	0.83
6.5	0.93
7	1.13
7.5	1.59

MM Size	Carat Weight
8	1.71
9	2.41
9.5	2.9
10	3.16
11	4.41
12	5.66
13	7.88
14	9.38
15	10.79
16	13.27
18	15.33

Trillion Cut

Shop Trillion Cut

MM Size	Carat Weight
3	0.12
3.5	0.16
3.75	0.19
4	0.23
4.25	0.27
4.5	0.31
4.75	0.37
5	0.42
5.25	0.49
5.5	0.55
5.75	0.64
6	0.7

MM Size	Carat Weight
6.25	0.75
6.5	0.91
6.75	0.98
7	1.1
7.5	1.21
8	1.75
9	2.35
11	3.66
12	4.9
13	6.42
15	9

Emerald Cut

Shop Emerald Cut

MM Size	Carat Weight
3 x 2	0.1
3.5 x 2	0.12
4 x 2	0.15
4 x 3	0.2
5 x 3	0.29
5.5 x 3.5	0.46
5.5 x 4	0.48
6 x 4	0.66
6.5 x 4.5	0.88
7 x 5	1.06
7.25 x 5.25	1.24
7.5 x 5.5	1.45
8 x 6	1.74
8.5 x 6.5	2.17

MM Size	Carat Weight
9 x 7	2.62
9.5 x 7.5	3.21
10 x 7	3.01
10 x 8	3.79
11 x 9	5.21
12 x 8	5.34
12 x 10	6
13 x 9	6.38
14 x 8	6.25
14 x 10	8.48
13 x 11	9.13
14 x 12	11.26
16 x 12	14.22

Triangle Cut

Shop Triangle Cut

MM Size	Carat Weight
2.5	0.08
3	0.12
3.5	0.18
4	0.25
4.25	0.32
4.5	0.37
4.75	0.42
5	0.45
5.25	0.53
5.5	0.66
5.75	0.71
6	0.76
6.25	0.86
6.5	0.94
6.75	1.02

MM Size	Carat Weight
7	1.11
7.25	1.32
7.5	1.45
7.75	1.69
8	1.79
8.25	1.86
9	2.15
9.25	2.54
9.75	3.25
10	3.52
11	4.74
12	6.03
13	8.12
14	9.83

Baguette Tapered Cut

Shop Baguette Tapered Cut

MM Size	Carat Weight
2 x 1.5 x 1	0.025
2.5 x 1.5 x 1	0.035
2.5 x 1.75 x 1	0.04
3 x 1.5 x 1	0.05
3 x 1.75 x 1.25	0.055
3 x 1.75 x 1.3	0.055
3 x 1.75 x 1.5	0.055
3 x 2 x 1	0.06
3 x 2 x 1.25	0.065
3 x 2 x 1.5	0.07
3 x 2 x 1.75	0.075
3 x 2.5 x 2	0.08
3.25 x 1.75 x 1	0.07
3.25 x 1.75 x 1.25	0.05
3.5 x 1.25 x 1	0.04
3.5 x 1.5 x 1	0.05
3.5 x 1.5 x 1.25	0.055
3.5 x 1.7 x 1.3	0.055
3.5 x 1.75 x 1	0.06
3.5 x 1.75 x 1.25	0.07
3.5 x 1.75 x 1.3	0.065
3.5 x 2 x 1.25	0.08
3.5 x 2 x 1.5	0.09
3.5 x 2.5 x 2	0.09
3.75 x 2 x 1.25	0.08
4 x 1.5 x 1	0.07
4 x 1.5 x 1.2	0.08
4 x 1.75 x 1.25	0.08
4 x 2 x 1.5	0.1
4 x 2.5 x 1.5	0.12
4 x 2.5 x 2	0.21
4 x 3 x 2	0.21
4.25 x 2 x 1.25	0.11

MM Size	Carat Weight
4.25 x 2 x 1.5	0.13
4.25 x 2.5 x 1.25	0.13
4.25 x 2.5 x 1.5	0.135
4.5 x 1.75 x 1.25	0.15
4.5 x 2 x 1.5	0.12
4.5 x 2.3 x 1.8	0.16
4.5 x 2.5 x 2	0.15
4.5 x 2.75 x 1.75	0.15
4.5 x 3 x 2	0.16
4.5 x 3 x 2.5	0.16
4.75 x 2.5 x 1.5	0.15
4.75 x 3 x 2	0.18
5 x 2 x 1	0.14
5 x 2 x 1.25	0.15
5 x 2 x 1.5	0.15
5 x 2.3 x 1.8	0.16
5 x 2.5 x 1.5	0.2
5 x 2.5 x 2	0.21
5 x 2.75 x 2	0.21
5 x 3 x 2	0.25
5 x 3.5 x 2	0.26
5 x 4 x 3.5	0.28
5.5 x 2 x 1.5	0.18
5.5 x 2.5 x 1.75	0.23
5.5 x 2.5 x 2	0.23
5.5 x 3 x 2	0.26
5.5 x 3 x 2.25	0.26
5.5 x 4 x 2.5	0.28
6 x 2 x 1.5	0.3
6 x 2.5 x 1.5	0.3
6 x 3 x 2	0.3
6.5 x 2.5 x 2	0.3
6.5 x 3 x 2	0.32

Baguette Straight Cut

Shop Baguette Straight Cut

MM Size	Carat Weight
2 x 1	0.02
2 x 1.5	0.04
2 x 1.75	0.04
2.25 x 1.75	0.04
2.25 x 2	0.045
2.5 x 1	0.045
2.5 x 1.25	0.047
2.5 x 1.5	0.05
2.5 x 1.75	0.055
2.5 x 2	0.055
2.75 x 1.5	0.055
2.75 x 1.75	0.06
2.75 x 2	0.06
2.75 x 2.5	0.065
3 x 1	0.05
3 x 1.25	0.055
3 x 1.5	0.06
3 x 1.75	0.08
3 x 2	0.1
3 x 2.5	0.13
3.25 x 1.25	0.06
3.25 x 1.5	0.065
3.25 x 1.75	0.08
3.25 x 2.5	0.14
3.5 x 1	0.065
3.5 x 1.25	0.07
3.5 x 1.5	0.07
3.5 x 1.75	0.08
3.5 x 2	0.13
3.5 x 2.5	0.15
3.5 x 3	0.15

MM Size	Carat Weight
3.75 x 1.5	0.14
3.75 x 2	0.145
4 x 1.25	0.075
4 x 1.5	0.08
4 x 1.75	0.11
4 x 2	0.14
4 x 3	0.2
4.5 x 1.5	0.1
4.5 x 1.75	0.14
4.5 x 2	0.17
4.5 x 2.5	0.2
4.5 x 3	0.285
4.5 x 3.5	0.3
4.75 x 1.5	0.27
4.75 x 2	0.28
5 x 1.5	0.14
5 x 1.75	0.15
5 x 2	0.19
5 x 2.5	0.24
5 x 3	0.3
5 x 3.5	0.33
5 x 4	0.4
5.5 x 1.75	0.16
5.5 x 2	0.18
5.5 x 2.5	0.23
5.5 x 3	0.3
5.5 x 3.5	0.33
6 x 1.75	0.28
6 x 2	0.3
6 x 2.5	0.33
6 x 3	0.4

Designing an engagement ring is quick and easy with this diamond size chart. The first thing that you’ll need to do is to choose your desired shape. Each shape has a unique style, brilliance and meaning.

After you decide on the right shape, it’s time to choose on the perfect carat size for you. Whether you want a round cut, cushion cut, oval, asscher, emerald, heart, or princess cut diamond alternative, we have it here for you.

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MM to carat weight conversion values