UK to Japanese hook sizes
UK crochet hook sizes converted to Japanese, with a link to the full detail page for every size.
Japanese sizes are not exact equivalents
Japanese 号 (gō) hooks step in their own increments — 4/0号 is 2.5 mm, while the nearest US hook,
C/2, is 2.75 mm. That quarter millimetre changes gauge in amigurumi. Where a Japanese pattern
names a 号 size, buy the millimetre size, not the lettered equivalent.
| UK | Japanese | Detail |
|---|---|---|
| 14 | 2/0号 | 2 mm |
| 12 | 4/0号 | 2.5 mm |
| 11 | 5/0号 | 3 mm |
| 9 | 6/0号 | 3.5 mm |
| 8 | 7/0号 | 4 mm |
| 7 | 7.5/0号 | 4.5 mm |
| 6 | 8/0号 | 5 mm |
| 5 | 9/0号 | 5.5 mm |
| 4 | 10/0号 | 6 mm |
| 2 | 7mm | 7 mm |
| 0 | 8mm | 8 mm |
Other hook charts
Last updated 2026-08-30.