Diamond Conversion Chart

Round Diamonds Carats to
Millimeters (Plus or Minus 10%)

Use these charts to convert your MM Size in Diamonds to Carats. Some of our digital micrometers will convert this automatically.

MM	CT		MM	CT
1	0.005		7	1.25
1.2	0.0075		7.2	1.33
1.3	0.01		7.4	1.5
1.5	0.015		7.6	1.6
1.7	0.02		7.8	1.75
1.8	0.025		8	1.9
2	0.03		8.2	2
2.1	0.035		8.4	2.15
2.2	0.04		8.6	2.25
2.4	0.05		8.8	2.5
2.5	0.06		9	2.65
2.7	0.07		9.2	2.85
2.8	0.08		9.4	3
2.9	0.09		9.6	3.15
3	0.1		9.8	3.35
3.1	0.11		10	3.5
3.2	0.12		10.2	3.75
3.3	0.14		10.4	4
3.4	0.15		10.6	4.25
3.5	0.16		10.8	4.45
3.6	0.17		11	4.75
3.7	0.18		11.2	5
3.8	0.2		11.4	5.25
3.9	0.22		11.6	5.5
4	0.23		11.75	5.75
4.1	0.25		11.8	5.81
4.2	0.3		11.9	6
4	0.33		12.1	6.25
4.5	0.35		12.5	7
4.6	0.38		12.85	7.5
4.8	0.4		13	7.75
4.9	0.43		13.1	8
5	0.47		13.25	8.23
5.2	0.5		13.4	8.5
5.4	0.6		13.5	8.75
5.5	0.63		13.65	9
5.6	0.65		13.75	9.2
5.8	0.75		14	9.75
6	0.8		14.5	10.34
6.2	0.85		15	12
6.4	0.95		15.4	12.92
6.5	1		15.5	13.17
6.6	1.1		16	14.5
6.8	1.17