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MM to Carat Weight Conversion

Diamond Nexus Gemstones

Click on the the cut to view its millimeter to carat conversion chart


  • Round
  • Princess
  • Asscher
  • Marquise
  • Radiant
  • Cushion
  • Pear
  • Oval
  • Heart
  • Trillion
  • Emerald
  • Triangle
  • Baguette
    Tapered
  • Baguette
    Straight
1215 Engagement: True Grown Diamonds

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

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 2 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

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

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

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
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