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.
About this Hook Needle Size Converter
Use this free Hook Needle Size Converter to get quick, accurate results directly in your browser. It is designed for everyday use with no signup, no downloads, and no account required. No signup is required, and the tool works on phones, tablets, and desktop browsers.