Well, this depends on many factors. View or knitting needle and crochet hook size guide for working with popular yarn weights such as double knit, 4 ply, chunky & more.
Ladies' Half Fisherman's Rib Pullover Chest Sizes 32-34 and 38-40
Milky Way, Yarn
Crochet Hook Sizes and Yarn Weights - Dora Does
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Crochet Hook Sizes - Everything You Need to Know - Crochet 365
Ravelry: Adult Saunter Poncho pattern by Tatsiana Matsiuk
Swedish-Influenced Raggsocks Pattern
Crochet Square Triangle Shawl - Blacker Yarns
Bronte Sister Mountain
All about sizes for knitting needles and crochet hooks
Shepherd Baby Set - Project Kit - Blacker Yarns
Where we once knitted: Grain
What Size Crochet Hook or Knitting Needle for what Ply Yarn