Hook & Needle Size Converter
Find any crochet hook or knitting needle size across US, metric, and UK systems.
Find My Size
Type any size — US letter, metric mm, or UK number — to find equivalents across both systems.
| US Size | Metric (mm) | UK / Canadian |
|---|
| US Size | Metric (mm) | UK / Canadian |
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How to Use This Tool
- Find My Size: Type any size in any system into the search box and instantly see matches across both crochet hooks and knitting needles, in all three measurement systems.
- Switch between the Crochet Hooks and Knitting Needles tabs to browse full reference tables.
- Use the filter boxes inside each tab to narrow down rows quickly.
Hooks vs. Needles — What Sizes Overlap?
Crochet hooks and knitting needles share the same metric (mm) shaft diameter system, so a 5mm hook and a 5mm (US8) needle are the same diameter. However, US numbering differs between the two tools — a "G/6" crochet hook is 4mm, while a "US6" knitting needle is also 4mm (they match!).
- UK/Canadian numbers are different for hooks vs. needles — always verify by mm.
- Steel crochet hooks use a separate numbering system not shown in the main table.