Carat is the term used to express the weight of a diamond, with one carat equaling 200 milligrams of actual weight.Usually abbreviated ct. Diamonds are measured in terms of weight, not size. The heavier the diamond, the greater the carat weight. Carat weight should not be confused with "karat," the term used to describe gold’s fineness or purity. The chart below is a guideline and does not represent exact size.
| Carats |
|
Diameter (mm) |
|
Carats |
|
Diameter (mm) |
|
| .005 |
|
1.0 |
|
1.25 |
|
7.0 |
| .0067 |
|
1.15 |
|
1.33 |
|
7.2 |
| .01 |
|
1.3 |
|
1.50 |
|
7.4 |
| .015 |
|
1.5 |
|
1.60 |
|
7.6 |
| .02 |
|
1.7 |
|
1.75 |
|
7.8 |
| .025 |
|
1.8 |
|
1.90 |
|
8.0 |
| .03 |
|
2.0 |
|
2.00 |
|
8.2 |
| .035 |
|
2.1 |
|
2.15 |
|
8.4 |
| .04 |
|
2.2 |
|
2.25 |
|
8.6 |
| .05 |
|
2.4 |
|
2.50 |
|
8.8 |
| .06 |
|
2.5 |
|
2.65 |
|
9.0 |
| .07 |
|
2.7 |
|
2.85 |
|
9.2 |
| .08 |
|
2.8 |
|
3.00 |
|
9.4 |
| .09 |
|
2.9 |
|
3.15 |
|
9.6 |
| .10 |
|
3.0 |
|
3.35 |
|
9.8 |
| .11 |
|
3.1 |
|
3.50 |
|
10.0 |
| .12 |
|
3.2 |
|
3.75 |
|
10.2 |
| .14 |
|
3.3 |
|
4.00 |
|
10.4 |
| .15 |
|
3.4 |
|
4.25 |
|
10.6 |
| .16 |
|
3.5 |
|
4.50 |
|
10.8 |
| .17 |
|
3.6 |
|
4.75 |
|
11.0 |
| .18 |
|
3.7 |
|
5.00 |
|
11.2 |
| .20 |
|
3.8 |
|
5.25 |
|
11.4 |
| .22 |
|
3.9 |
|
5.50 |
|
11.6 |
| .23 |
|
4.0 |
|
5.75 |
|
11.75 |
| .25 |
|
4.1 |
|
5.81 |
|
11.8 |
| .30 |
|
4.2 |
|
6.00 |
|
11.9 |
| .33 |
|
4.4 |
|
6.25 |
|
12.1 |
| .35 |
|
4.5 |
|
7.00 |
|
12.5 |
| .38 |
|
4.6 |
|
7.50 |
|
12.85 |
| .40 |
|
4.8 |
|
7.75 |
|
13.00 |
| .43 |
|
4.9 |
|
8.00 |
|
13.1 |
| .47 |
|
5.0 |
|
8.23 |
|
13.25 |
| .50 |
|
5.2 |
|
8.50 |
|
13.4 |
| .60 |
|
5.4 |
|
8.75 |
|
13.5 |
| .63 |
|
5.5 |
|
9.00 |
|
13.65 |
| .65 |
|
5.6 |
|
9.20 |
|
13.75 |
| .75 |
|
5.8 |
|
9.75 |
|
14.0 |
| .80 |
|
6.0 |
|
10.34 |
|
14.5 |
| .85 |
|
6.2 |
|
12.00 |
|
15.0 |
| .95 |
|
6.4 |
|
12.92 |
|
15.4 |
| 1.00 |
|
6.5 |
|
13.17 |
|
15.5 |
| 1.10 |
|
6.6 |
|
14.50 |
|
16.0 |
| 1.17 |
|
6.8 |
|
|
|
|
Source: Gemological Institute of America (GIA) |
