Crochet How-To: Matching Crochet Yarn and Hook

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Matching your yarn and hook is one of the most important beginner's lesson in crochet. There are two standards in hook sizes, Japanese and International although I am more familiar with the Japanese sizes and I find these hooks more cost-effective being double-ended (2 sizes in one hook!).

I found this very informative blog by snufykin where she lists down crochet hook sizes matching yarn weights. Check the chart here. Thanks to iheartcrochet blog for the link to snufykin.

Converted the chart in that site to text for your easy reference:

weight 3/0 4/0 5/0 6/0 7/0 8/0 10/0 7mm 8mm 10mm
2-ply lace •
3-ply • •
4-ply finger • •
sport • •
sport/dk • • •
dk • •
bulky • • •