Hook size conversion chart
| Metric (mm) | US | UK |
|---|---|---|
| 2.0 mm | B/1 | 14 |
| 2.25 mm | B/1 | 13 |
| 2.75 mm | C/2 | 12 |
| 3.25 mm | D/3 | 11 |
| 3.5 mm | E/4 | 9 |
| 3.75 mm | F/5 | 8 |
| 4.0 mm | G/6 | 8 |
| 4.5 mm | 7 | 7 |
| 5.0 mm | H/8 | 6 |
| 5.5 mm | I/9 | 5 |
| 6.0 mm | J/10 | 4 |
| 6.5 mm | K/10.5 | 3 |
| 8.0 mm | L/11 | 0 |
| 9.0 mm | M/N-13 | 00 |
| 10.0 mm | N/P-15 | 000 |
Notes: hook sizing can vary slightly by brand. When in doubt, measure your hook or prioritize the metric size listed on your pattern.
How to choose the right crochet hook size
The “right” hook size is the one that gives you the fabric you want. Patterns usually specify a hook size and a gauge. If you match gauge, your finished dimensions will match the pattern. If you want a denser fabric (like for amigurumi), you may intentionally size down.
- For drape: go up a size for a softer, airier fabric.
- For structure: go down a size for tighter stitches.
- For speed: larger hooks work up faster but can look looser.
If you're new to gauge, start with our how to crochet guide and practice a small swatch before committing to a big project.
Yarn weight to hook size recommendations
| Yarn weight | Suggested hooks | Great for |
|---|---|---|
| Lace (0) | 1.5–2.25 mm | Doilies, fine shawls, delicate lace |
| Fingering (1) | 2.25–3.25 mm | Socks, lightweight shawls, baby items |
| Sport (2) | 3.25–3.75 mm | Light garments, hats, baby blankets |
| DK (3) | 3.75–4.5 mm | Cardigans, blankets, accessories |
| Worsted (4) | 4.5–6.0 mm | Blankets, hats, scarves, amigurumi |
| Bulky (5) | 6.0–8.0 mm | Quick hats, cowls, chunky blankets |
| Super Bulky (6) | 8.0–12.0 mm | Statement scarves, arm-knit look throws |