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June 21st 2022

Diamond Size Chart

By Devin Jones

How big is a 1 carat diamond in millimeters? How many carats is a 5 millimeter diamond? The below diamond size charts will help you convert carat weight to millimeters and vice versa.

Round Diamond Size Chart Round
Cushion Diamond Size Chart Cushion
Emerald Diamond Size Chart Emerald
Oval Diamond Size Chart Oval
Princess Diamond Size Chart Princess
Pear Diamond Size Chart Pear
Radiant Diamond Size Chart Radiant
Asscher Diamond Size Chart Asscher
Heart Diamond Size Chart Heart
Marquise Diamond Size Chart Marquise

Diamond Carat Size Chart

The below diamond carat size chart is for round cut diamonds.

Diamond Carat Weight Diamond MM Size Surface Area (sq. mm)
0.3 ct. 4.30 14.52
0.4 ct. 4.73 17.59
0.5 ct. 5.10 20.41
0.6 ct. 5.42 23.04
0.7 ct. 5.70 25.53
0.8 ct. 5.96 27.90
0.9 ct. 6.20 30.17
1 ct. 6.42 32.37
1.1 ct. 6.63 34.49
1.2 ct. 6.82 36.54
1.3 ct. 7.01 38.54
1.4 ct. 7.18 40.49
1.5 ct. 7.35 42.39
1.6 ct. 7.51 44.25
1.7 ct. 7.66 46.07
1.8 ct. 7.81 47.86
1.9 ct. 7.95 49.61
2 ct. 8.08 51.34
2.1 ct. 8.22 53.03
2.2 ct. 8.35 54.70
2.3 ct. 8.47 56.34
2.4 ct. 8.59 57.96
2.5 ct. 8.71 59.55
2.6 ct. 8.82 61.13
2.7 ct. 8.93 62.68
2.8 ct. 9.04 64.22
2.9 ct. 9.15 65.74
3 ct. 9.25 67.24
3.1 ct. 9.35 68.72
3.2 ct. 9.45 70.19
3.3 ct. 9.55 71.64
3.4 ct. 9.65 73.08
3.5 ct. 9.74 74.50
3.6 ct. 9.83 75.91
3.7 ct. 9.92 77.31
3.8 ct. 10.01 78.69
3.9 ct. 10.10 80.06
4 ct. 10.18 81.43
4.1 ct. 10.27 82.77
4.2 ct. 10.35 84.11
4.3 ct. 10.43 85.44
4.4 ct. 10.51 86.76
4.5 ct. 10.59 88.06
4.6 ct. 10.67 89.36
4.7 ct. 10.74 90.65
4.8 ct. 10.82 91.93
4.9 ct. 10.89 93.20
5 ct. 10.97 94.46

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