Princess Cut Diamond Carat Size Chart

We’ve estimated the average side length (mm) for princess cut diamonds using measurements listed on James Allen. Relative sizes for each carat weight are illustrated in the figure below the table.

Average Side Length of Princess Cut Diamonds
Carat	Side Length	SD	N
0.3 ct	3.72 mm	0.07	183
0.4 ct	4.09 mm	0.088	124
0.5 ct	4.37 mm	0.107	417
0.6 ct	4.6 mm	0.106	111
0.7 ct	4.84 mm	0.116	519
0.8 ct	5.03 mm	0.122	273
0.9 ct	5.22 mm	0.11	552
1.0 ct	5.46 mm	0.136	1283
1.1 ct	5.7 mm	0.136	70
1.2 ct	5.8 mm	0.169	392
1.3 ct	6 mm	0.162	84
1.4 ct	6.2 mm	0.187	53
1.5 ct	6.27 mm	0.158	311
1.6 ct	6.44 mm	0.135	31
1.7 ct	6.55 mm	0.152	153
1.8 ct	6.67 mm	0.129	46
1.9 ct	6.85 mm	0.18	31
2.0 ct	6.93 mm	0.158	197
2.1 ct	7.09 mm	0.121	13
2.2 ct	7.17 mm	0.103	9
2.3 ct	7.3 mm	0.15	6
2.4 ct	7.28 mm	0.08	5
2.5 ct	7.42 mm	0.175	50
2.6 ct	7.54 mm	0.124	6
2.7 ct	7.63 mm	0.142	11
2.8 ct	7.81 mm	0.12	4
2.9 ct	NA mm	NA	0
3.0 ct	7.93 mm	0.185	51
3.1 ct	7.89 mm	0.119	5
3.2 ct	8.15 mm	0.163	2
3.3 ct	NA mm	NA	0
3.4 ct	8.26 mm	0	1
3.5 ct	8.36 mm	0.166	8