MM to Carat Weight Conversion Charts

Round

European, Mine, Portuguese, Lonestar, Sunburst

Size (mm) CZ ct wt Diamond ct wt
1.25 0.013 0.010
1.25 0.013 0.010
1.50 0.023 0.015
1.75 0.037 0.020
2.00 0.06 0.03
2.25 0.08 0.04
2.50 0.10 0.05
2.75 0.15 0.08
3.00 0.18 0.11
3.50 0.29 0.17
4.00 0.43 0.25
4.50 0.61 0.36
5.00 0.79 0.46
5.50 1.13 0.66
6.00 1.43 0.84
6.50 1.75 1.03
7.00 2.17 1.28
7.50 2.84 1.67
8.00 3.46 2.04
8.50 4.13 2.43
9.00 4.68 2.75
9.50 5.69 3.35
10.00 6.58 3.87
10.50 7.50 4.41
11.00 8.35 4.91
11.50 9.94 5.85
12.00 11.62 6.84
12.50 12.52 7.36
13.00 14.47 8.51
13.50 16.20 9.53
14.00 17.84 10.49
15.00 21.92 12.89
16.00 27.25 16.03
17.00 33.55 19.74
18.00 38.60 22.71
19.00 41.78 24.58
20.00 50.22 29.54
22.00 67.43 39.66
25.00 99.18 58.34
30.00 181.77 106.92
40.00 374.15 220.09

Princess

Quadrillion, Cushion, Asscher, Flanders

Size (mm) CZ ct wt Diamond ct wt
3.00 0.30 0.18
3.50 0.50 0.29
4.00 0.66 0.39
4.50 0.95 0.56
5.00 1.21 0.71
5.50 1.68 0.99
6.00 2.10 1.24
6.50 2.71 1.59
7.00 3.33 1.96
7.50 4.08 2.40
8.00 5.12 3.01
8.50 6.24 3.67
9.00 7.01 4.12
9.50 8.65 5.09
10.00 9.56 5.62
11.00 12.64 7.44
12.00 16.18 9.52
13.00 21.86 12.86
14.00 25.75 15.15
16.00 40.94 24.08
18.00 55.14 32.44
20.00 72.52 42.66
22.00 99.73 58.66
3.00 0.30 0.18

Emerald

Size (mm) CZ ct wt Diamond ct wt
5 x 3 0.50 0.29
6 x 4 1.13 0.66
6.5 x 4.5 1.49 0.88
7 x 5 1.81 1.06
8 x 6 2.95 1.74
8.5 x 6.5 3.69 2.17
9 x 7 4.46 2.62
9.5 x 7.5 5.46 3.21
10 x 8 6.44 3.79
12 x 8 8.13 4.78
11 x 9 8.85 5.21
13 x 9 10.84 6.38
12 x 10 11.82 6.95
14 x 10 14.42 8.48
13 x 11 15.52 9.13
14 x 12 19.15 11.26
15 x 11 19.51 11.48
16 x 12 24.18 14.22
18 x 13 32.86 19.33
20 x 15 44.03 25.90

Oval

Size (mm) CZ ct wt Diamond ct wt
5x3 0.35 0.21
5x4 0.55 0.32
6x4 0.73 0.43
6x5 1.04 0.61
7x5 1.30 0.76
7.5x5.5 1.67 0.98
8x6 2.06 1.21
9x6 2.40 1.41
9x7 3.16 1.86
10x8 4.31 2.54
10.5x8.5 4.90 2.88
12x8 5.09 2.99
11x9 6.40 3.85
12x10 8.59 5.05
14x10 9.87 5.81
13x11 10.28 6.05
14x12 13.96 8.21
15x12 14.89 8.76
16x12 15.84 9.32
18x13 21.86 12.86
20x15 32.17 18.92
22x16 40.84 24.02

Heart

Size (mm) CZ ct wt Diamond ct wt
4.00 0.40 0.24
4.50 0.57 0.34
5.00 0.75 0.44
5.50 1.03 0.61
6.00 1.25 0.74
6.25 1.41 0.83
6.50 1.58 0.93
7.00 1.92 1.13
7.50 2.71 1.59
8.00 2.90 1.71
9.00 4.10 2.41
10.00 5.38 3.16
11.00 7.50 4.41
12.00 9.63 5.66
13.00 13.40 7.88
14.00 15.95 9.38
15.00 18.34 10.79
16.00 22.56 13.27
18.00 35.50 20.88
20.00 42.01 24.71

Marquise

Size (mm) CZ ct wt Diamond ct wt
6x3 0.41 0.24
6.5x3.5 0.53 0.31
7x3.5 0.60 0.35
8x3.5 0.69 0.41
8x4 0.80 0.47
9x4.5 1.20 0.71
10x5 1.62 0.95
11x5.5 2.12 1.25
12x6 2.75 1.62
13x6.5 3.60 2.11
14x7 4.22 2.48
15x7.5 5.25 3.09
16x8 6.57 3.86
17x8.5 8.30 4.88
18x9 9.61 5.65
20x10 13.49 7.94
22x11 16.28 9.58
30x15 36.50 21.00

Pear

Size (mm) CZ ct wt Diamond ct wt
5x4 0.60 0.35
6x4 0.67 0.39
6.5x4.5 0.97 0.57
7x5 1.21 0.71
8x5 1.38 0.81
8.5x5.5 1.83 1.08
9x6 2.26 1.33
9x7 2.98 1.75
10x7 3.06 1.80
10x8 4.19 2.46
11x7.5 4.44 2.61
11x8 5.10 3.00
12x8 5.06 2.98
12x9 5.85 3.44
13x8 5.04 2.98
14x8 5.90 3.47
13x9 6.99 4.11
14x9 7.01 4.12
15x9 8.60 5.06
14x10 9.20 5.41
13x11 9.61 5.65
15x10 9.78 5.75
16x10 10.66 6.27
17x10 10.99 6.46
15x11 12.52 7.36
17x11 13.86 8.05
18x11 13.84 8.14
16x12 15.29 8.99
18x12 15.90 9.35
18x13 19.83 11.66
19x12 17.00 10.00
19x13 20.79 12.23
20x14 24.92 14.66
23x13 25.89 15.23
22x14 26.30 15.47
20x15 28.65 16.85
23x14 26.00 25.29
25x15 30.02 17.66
25x20 64.00 37.65

Trillion

Size (mm) CZ ct wt Diamond ct wt
3.50 0.28 0.16
4.00 0.39 0.23
4.50 0.53 0.31
5.00 0.72 0.42
5.50 0.93 0.55
6.00 1.19 0.70
6.50 1.55 0.91
7.00 1.87 1.10
7.50 2.06 1.21
8.00 2.97 1.75
8.500 3.00 1.76
9.00 3.99 2.35
10.00 5.30 3.12
11.00 6.22 3.66
12.00 8.33 4.90
13.00 10.91 6.42