Standard Crochet hook sizes
| USA | English | Metric |
| -- | 000 | 10.0mm |
| N | 00 | 9.00mm |
| -- | 0 | 8.00mm |
| K-10 1/2 | 2 | 7.00mm |
| 10 1/4 | 3 | 6.50mm |
| J-10 | 4 | 6.00mm |
| I-9 | 5 | 5.50mm |
| H-8 | 6 | 5.00mm |
| 7 | 7 | 4.50mm |
| G-6 | 8 | 4.00mm |
| F-5 | 9 | 3.75mm |
| E-4 | 9 | 3.50mm |
| D-3 | 10 | 3.25mm |
| C-2 | 12 | 2.75mm |
| B-1 | 13 | 2.25mm |
| B-1 | 14 | 2.00mm |
| 5 steel | - | 1.75mm |
8 steel - 1.25mm
10 steel - 1.00mm
