AJS Diamonds Weight Chart

This chart shows the relationship between size (diameter in millimeters) and carat weight for round diamonds.
 
Round Diamonds Round Diamonds
width (mm)width (inch)Weightwidth (mm)width (inch)Weight
1.0 mm .039 inch .005 carat 4.8 mm   .40 carat
1.2 mm   .008 carat 4.9 mm   .43 carat
1.3 mm   .01 carat 5.0 mm .197 inch .47 carat
1.5 mm   .015 carat 5.2 mm .205 inch 1/2 carat
1.7 mm   .02 carat 5.4 mm   .60 carat
1.8 mm   .025 carat 5.5 mm   .63 carat
2.0 mm .079 inch .03 carat 5.6 mm   .65 carat
2.1 mm   .035 carat 5.8 mm .228 inch 3/4 carat
2.2 mm   .04 carat 6.0 mm .236 inch .80 carat
2.4 mm   .05 carat 6.2 mm   .85 carat
2.5 mm   .06 carat 6.4 mm   .95 carat
2.7 mm   .07 carat 6.5 mm .255 inch
or 1/4 inch		 1.00 carat
2.8 mm   .08 carat 6.6 mm   1.10 carat
2.9 mm   .09 carat 6.8 mm   1.17 carat
3.0 mm .118 inch 1/10 carat 7.0 mm .276 inch 1-1/4 carat
3.1 mm   .11 carat 7.2 mm   1.33 carat
3.2 mm .125 inch
or 1/8 inch		 .12 carat 7.4 mm .291 inch 1-1/2 carat
3.3 mm   .14 carat 7.6 mm   1.60 carat
3.4 mm   .15 carat 7.8 mm .307 inch 1.75 carat
3.5 mm   .16 carat 8.0 mm .315 inch 1.90 carat
3.6 mm   .17 carat 8.2 mm 323 inch 2.00 carat
3.7 mm   .18 carat 8.4 mm   2.15 carat
3.8 mm .150 inch 1/5 carat 8.6 mm .338 inch 2.25 carat
3.9 mm   .22 carat 8.8 mm .346 inch 2.50 carat
4.0 mm .158 inch .23 carat 9.0 mm .354 inch 2.65 carat
4.1 mm .162 inch 1/4  carat 9.2 mm   2.85 carat
4.2 mm   .30 carat 9.4 mm .370 inch 3.00 carat
4.4 mm .173 inch .33 carat 9.6 mm   3.15 carat
4.5 mm   .35 carat 9.8 mm   3.35 carat
4.6 mm .181 inch 1/3 carat 10.0 mm .394 inch 3-1/2 carat