Hobbyist reference
Hook & Needle Size Converter
Crochet hook and knitting needle sizes across US, metric (mm), and UK/Canada. Metric is the sizing that never changes, US letters and UK numbers vary a little between charts, so treat this as a solid reference, not gospel.
Hook size
4 mm
US G-6 · UK/Canada 8
| mm | US | UK/CA |
|---|---|---|
| 2.25 | B-1 | 13 |
| 2.75 | C-2 | 12 |
| 3.25 | D-3 | 10 |
| 3.5 | E-4 | 9 |
| 3.75 | F-5 | 9 |
| 4 | G-6 | 8 |
| 4.5 | 7 | 7 |
| 5 | H-8 | 6 |
| 5.5 | I-9 | 5 |
| 6 | J-10 | 4 |
| 6.5 | K-10.5 | 3 |
| 8 | L-11 | 0 |
| 9 | M/N-13 | 00 |
| 10 | N/P-15 | 000 |
| 12 | P/Q | — |
| 15 | Q | — |
| 16 | S | — |