Needle and Hook Conversion Chart

Actual size (mm.) US needle size Equivalent US hook size Equivalent UK size
2 mm. 0 - 14
2.25 mm. 1 B 13
2.5 mm. 1.5 - 12
2.75 mm. 2 C 12
3 mm. 2.5 - 11
3.25 mm. 3 D 10
3.5 mm. 4 E 9
3.75 mm. 5 F 9
4 mm. 6 G 8
4.5 mm. 7 - 7
5 mm. 8 H 6
5.5 mm. 9 I 5
6 mm. 10 J 4
6.5 mm. 10.5 K 3
7 mm. 10.75 - 2
8 mm. 11 L 0
9 mm. 13 M 0
10 mm. 15 N 0
12 mm. 17 - -
15 mm. 19 - -
20 mm. 35 - -
50 mm. 50 - -