Crochet hook sizes and yarn weight pair up in a fairly predictable pattern, from tiny steel hooks for lace weight up to jumbo hooks for super bulky yarn. I keep this chart bookmarked since I still forget the exact pairing for weights I don’t use often.
The full pairing chart
- Lace (weight 0): 1.5mm to 2.25mm, steel or fine hooks.
- Fingering to sport (weight 1-2): 2.25mm to 3.25mm.
- DK (weight 3): 3.5mm to 4.0mm.
- Worsted (weight 4): 5.0mm to 5.5mm.
- Bulky (weight 5): 6.5mm to 9mm.
- Super bulky (weight 6): 9mm to 15mm.
Why I still swatch every time
This chart gives a starting point, not a guarantee. My own gauge runs tighter than average, so I regularly need a half size larger than the chart suggests to match a pattern’s stated measurements.
Frequently asked questions
What hook size goes with worsted weight yarn?
A 5.0mm (H-8) to 5.5mm (I-9) hook is the standard pairing for worsted weight, the most common yarn weight for beginner patterns.
Does yarn weight number match hook size number?
No, the two numbering systems are unrelated. Always check a pairing chart rather than assume weight 4 yarn needs a size 4 hook, a mistake I made myself early on.
See the mm to US and UK hook chart too
Cross-reference hook letters and UK sizes alongside yarn weight.