MM to carat weight conversion values

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

MM Size Carat Weight
0.8 0.0025
1 0.005
1.10 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

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

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

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

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

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
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
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
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

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

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

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

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

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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