Free tool
Crochet hook size chart and converter
Type the size printed on your hook, in millimeters, US letters or old UK numbers, and see it in every system with the yarn weights it suits. The full chart is just below.
Loading the tool...
Crochet hook sizes from 2 mm to 30 mm
| Metric | US | UK / Canada (old) | Yarn weights it suits |
|---|---|---|---|
| 2 mm | · | 14 | · |
| 2.25 mm | B-1 | 13 | 0 Lace, 1 Super fine |
| 2.5 mm | · | 12 | 1 Super fine |
| 2.75 mm | C-2 | · | 1 Super fine |
| 3 mm | · | 11 | 1 Super fine |
| 3.25 mm | D-3 | 10 | 1 Super fine |
| 3.5 mm | E-4 | 9 | 1 Super fine, 2 Fine |
| 3.75 mm | F-5 | · | 2 Fine |
| 4 mm | G-6 | 8 | 2 Fine |
| 4.5 mm | 7 | 7 | 2 Fine, 3 Light |
| 5 mm | H-8 | 6 | 3 Light |
| 5.5 mm | I-9 | 5 | 3 Light, 4 Medium |
| 6 mm | J-10 | 4 | 4 Medium |
| 6.5 mm | K-10½ | 3 | 4 Medium, 5 Bulky |
| 7 mm | · | 2 | 5 Bulky |
| 8 mm | L-11 | 0 | 5 Bulky |
| 9 mm | M/N-13 | 00 | 5 Bulky, 6 Super bulky |
| 10 mm | N/P-15 | 000 | 6 Super bulky |
| 11.5 mm | P-16 | · | 6 Super bulky |
| 12 mm | · | · | 6 Super bulky |
| 15 mm | P/Q | · | 6 Super bulky, 7 Jumbo |
| 16 mm | Q | · | 7 Jumbo |
| 19 mm | S | · | 7 Jumbo |
| 25 mm | T/U/X | · | 7 Jumbo |
| 30 mm | T/X | · | 7 Jumbo |
US sizes from the Craft Yarn Council chart. A dot means that size has no agreed name in that system. Steel thread hooks are numbered differently by each maker and are not listed.
How to use it
- Find the size on the hook's handle or thumb rest. Most hooks print millimeters; many US hooks print a letter and a number, like G-6.
- Choose the system and type the size: 4, G-6, G and UK 8 all work.
- Use the yarn weights line to check a hook against your yarn's label.
Which hook size for amigurumi?
Millimeters are the one size that means the same everywhere, which is why most patterns and hooks list them. US letters are common in North America, and old UK and Canadian hooks used numbers where a smaller number is a bigger hook.
For amigurumi, crocheters usually go one or two sizes smaller than the yarn label suggests. With worsted (medium, 4) yarn, a 3.5 mm or 4 mm hook makes stitches tight enough that the stuffing doesn't show through. Every Yon kit comes with a hook matched to its yarn.
Questions crocheters ask
What size is a G crochet hook?
A US G-6 hook is 4 mm. Some brands also sell a G at 4.25 mm, so check the millimeters on the handle if your stitches look off.
What hook size goes with worsted weight yarn?
The Craft Yarn Council suggests 5.5 to 6.5 mm for worsted (medium, 4) yarn. For amigurumi, go smaller: 3.5 to 4 mm keeps the stitches tight.
Is a 4 mm hook the same as a G hook?
Yes. 4 mm is a US G-6 and an old UK 8.
Why are old UK hook numbers backwards?
They came from the steel wire gauge, where a higher number is a thinner wire. So a UK 14 is a small 2 mm hook and a UK 000 is 10 mm.
Learn to crochet, stitch by stitch
Yon video lessons film every stitch up close, round by round, for right and left hand. Every tool on this page is also in the Yon Crochet app, with your projects and a row counter that counts out loud.