Need some help converting between hook sizes?
Crochet hooks come in many sizes and it’s important to have the right size for your project. Sometimes it’s a bit tricky to know which size that is because there is more than one kind of sizing system for crochet hooks, US, UK, and metric.
Most crochet hooks have the size printed on the handle, but if your hook says “B” and your pattern or yarn ball says “5mm” how should you know if that hook is the right one?!
Well, you could learn which letters correspond to which number, or you could click the link to download my crochet hook size conversion chart
If you just want to take a quick look and be done with it, use the table below!
| Millimeter | US | UK |
|---|---|---|
| 2mm | 0 | 14 |
| 2,25mm | B-1 | 13 |
| 2,5mm | – | – |
| 2,75mm | C-2 | 12 |
| 3mm | D-3 | 11 |
| 3,25mm | – | 10 |
| 3,5mm | E-4 | – |
| 3,75mm | F-5 | 9 |
| 4mm | G-6 | 8 |
| 4,25mm | G | – |
| 4,5mm | 7 | 7 |
| 5mm | H-8 | 6 |
| 5,25mm | I | – |
| 5,5mm | I-9 | 5 |
| 5,75mm | J | – |
| 6mm | J-10 | 4 |
| 6,5mm | K-10,5 | 3 |
| 7mm | – | 2 |
| 7,5mm | – | 1 |
| 8mm | L-11 | 0 |
| 9mm | M-N-13 | 00 |
| 10mm | N-P-15 | 000 |
| 11,5mm | P-16 | – |
| 12mm | – | – |
| 15mm | P-Q-19 | – |
| 15,75mm | Q | – |
| 16 | Q | – |
| 19mm | S-35 | – |
| 25mm | T-U-X-50 | – |
| 30mm | T-X | – |
Your next read!
––> Crochet project planner pages
––> Best labels for knit and crochet garments
––> Crochet a cute bag for Barbie!