Complete Crochet Hook Size Chart
| Metric (mm) | US Letter | US Number | Best Yarn Weight |
|---|---|---|---|
| 2.25 | B | 1 | Lace, Fingering |
| 2.75 | C | 2 | Fingering, Sport |
| 3.25 | D | 3 | Sport, DK |
| 3.5 | E | 4 | DK |
| 3.75 | F | 5 | DK |
| 4.0 | G | 6 | DK, Worsted |
| 4.5 | 7 | 7 | Worsted |
| 5.0 | H | 8 | Worsted |
| 5.5 | I | 9 | Worsted, Aran |
| 6.0 | J | 10 | Bulky |
| 6.5 | K | 10.5 | Bulky |
| 8.0 | L | 11 | Super Bulky |
| 9.0 | M/N | 13 | Super Bulky |
| 10.0 | N/P | 15 | Super Bulky, Jumbo |
| 12.0 | P/Q | 16 | Jumbo |
| 15.0 | Q | 19 | Jumbo |
| 16.0 | Q | 19 | Jumbo |
| 19.0 | S | 35 | Jumbo |
Recommended Hook by Yarn Weight
| Yarn Weight | Hook Size (mm) | Hook Size (US) |
|---|---|---|
| Lace (#0) | 1.5-2.25 | Steel 6-B |
| Fingering (#1) | 2.25-3.25 | B-D |
| Sport (#2) | 3.25-3.75 | D-F |
| DK (#3) | 3.75-4.5 | F-7 |
| Worsted (#4) | 4.5-5.5 | 7-I |
| Bulky (#5) | 5.5-8.0 | I-L |
| Super Bulky (#6) | 8.0-12.0 | L-P/Q |
| Jumbo (#7) | 12.0-25.0 | P/Q and up |
FAQ
Why are crochet hook sizes so confusing?
Crochet hooks use three different numbering systems that evolved independently. The US letter system (B-S) is most common in North America. The metric system (mm) is the most precise and is used internationally. Some older patterns use the US number system.
Are crochet hooks the same as knitting needles?
No. While the metric sizes overlap, a 5mm crochet hook and 5mm knitting needle serve different purposes. Crochet hooks have a hook at the end; knitting needles are pointed. The same yarn weight may call for different hook vs. needle sizes.
What hook should I use if my gauge is off?
If your stitches are too tight (too many per inch), go up one hook size. If too loose (too few per inch), go down one size. Some crocheters consistently work tighter or looser than average — learn your tendency and adjust accordingly.