Hook sizing is not standardised across countries, and the same hook can carry three different names. The metric measurement is the only one that is unambiguous, so when a pattern gives a size in millimetres, use that.
Manufacturers also vary slightly within a nominal size. Whichever chart you work from, the hook that matters is the one that gives you the pattern’s gauge – treat these conversions as a starting point and swatch to confirm.
| US | English | Metric (mm) |
|---|---|---|
| – | 000 | 10.0 |
| N | 00 | 9.00 |
| – | 0 | 8.00 |
| K-10 1/2 | 2 | 7.00 |
| 10 1/4 | 3 | 6.50 |
| J-10 | 4 | 6.00 |
| I-9 | 5 | 5.50 |
| H-8 | 6 | 5.00 |
| 7 | 7 | 4.50 |
| G-6 | 8 | 4.00 |
| F-5 | 9 | 3.75 |
| E-4 | 9 | 3.50 |
| D-3 | 10 | 3.25 |
| C-2 | 12 | 2.75 |
| B-1 | 13 | 2.25 |
| B-1 | 14 | 2.00 |
| 5 steel | - | 1.75 |
| 7 steel | - | 1.50 |
| 8 steel | - | 1.25 |
| 10 steel | - | 1.00 |
A dash means there is no equivalent size in that system.
Crochet Abbreviations
| Abbreviation | Meaning |
|---|---|
| beg | beginning |
| bpdc | backpost double crochet |
| CC | Contrasting Color |
| ch | chain |
| cl | cluster |
| dc | double crochet |
| dec | decrease |
| dtr | double treble crochet |
| fpdc | front post double crochet |
| hdc | half double crochet |
| inc | increase |
| lp(s) | loop(s) |
| MC | Main Color |
| p | picot |
| rep | repeat |
| rnd | round |
| RS | Right Side facing you |
| sk | skip |
| st | stitch |
| sc | single crochet |
| sp | space |
| tog | together |
| tr | treble |
| woh | wool over hook |
| WS | Wrong Side facing you |
| yoh | yarn over hook |
