When looking up patterns from the United States, some UK crocheters are left wondering what the heck is a D sized hook. You may come across a few different terminologies for crochet hook sizes, not just for the US but also for Canadian crochet patterns. Here’s a handy crochet hook conversion chart so you can tell your C’s from you 13’s.
Crochet hook conversion chart
| Metric size (mm) | UK/Canadian size | US size |
| 2.0mm | 14 | n/a |
| 2.25mm | 13 | B/1 |
| 2.5mm | 12 | n/a |
| 2.75mm | n/a | C/2 |
| 3.0mm | 11 | n/a |
| 3.25mm | 10 | D/3 |
| 3.5mm | 9 | E/4 |
| 3.75mm | n/a | F/5 |
| 4.0mm | 8 | G/6 |
| 4.5mm | 7 | 7 |
| 5.0mm | 6 | H/8 |
| 5.5mm | 5 | I/9 |
| 6.0mm | 4 | J/10 |
| 6.5mm | 3 | K/10.5 |
| 7.0mm | 2 | n/a |
| 8.0mm | 0 | L/11 |
| 9.0mm | 00 | M/13 |
| 10.0mm | 000 | N/15 |
Not quite the crochet hook conversion chart you were looking for? Let me know if there’s anything else I can add to this chart.
If you need help translating crochet stitches, take a look at my crochet stitch conversion chart.
Want to convert wool and yarn weights? Check out my yarn weight conversion chart.