Knitting needle size chart
Metric, US and old UK knitting needle sizes side by side, with the yarn weights each size suits.
Updated
Needle size conversion chart
| Metric | US | UK / Canada | Yarn weight |
|---|---|---|---|
| 1.5 mm | 000 | — | Lace |
| 1.75 mm | 00 | — | Lace |
| 2 mm | 0 | 14 | Lace |
| 2.25 mm | 1 | 13 | Lace, Super fine |
| 2.5 mm | 1½ | — | Super fine |
| 2.75 mm | 2 | 12 | Super fine |
| 3 mm | 2½ | 11 | Super fine |
| 3.25 mm | 3 | 10 | Super fine, Fine |
| 3.5 mm | 4 | — | Fine |
| 3.75 mm | 5 | 9 | Fine, Light |
| 4 mm | 6 | 8 | Light |
| 4.5 mm | 7 | 7 | Light, Medium |
| 5 mm | 8 | 6 | Medium |
| 5.5 mm | 9 | 5 | Medium, Bulky |
| 6 mm | 10 | 4 | Bulky |
| 6.5 mm | 10½ | 3 | Bulky |
| 7 mm | — | 2 | Bulky |
| 7.5 mm | — | 1 | Bulky |
| 8 mm | 11 | 0 | Bulky, Super bulky |
| 9 mm | 13 | 00 | Super bulky |
| 10 mm | 15 | 000 | Super bulky |
| 12 mm | 17 | — | Super bulky |
| 15 mm | 19 | — | Jumbo |
| 19 mm | 35 | — | Jumbo |
| 25 mm | 50 | — | Jumbo |
How to read needle sizes
The metric size is the needle's diameter in millimetres, so it is the most reliable. US sizes are numbers that get bigger as the needle gets thicker. Old UK and Canadian sizes run the other way. Some sizes exist in only one or two systems, shown as "—".
If you have a needle with no markings, a needle gauge (a card with measured holes) tells you the metric size. Push the needle through the smallest hole it fits.
Common questions
What size is a US 8 knitting needle?
A US 8 needle is 5 mm, which is UK size 6. It is a common size for worsted and aran yarn.
What knitting needle size is best for beginners?
Start with 5–6 mm (US 8–10) needles and worsted or aran yarn. The stitches are big enough to see clearly, and the fabric grows quickly.
Why are old UK needle numbers backwards?
Old UK sizes came from wire gauges, where a higher number means thinner wire. So a UK 14 is a thin 2 mm needle and a UK 000 is a thick 10 mm one. The US system goes the other way.
Does needle length or type change the size?
No. Straight, circular and double-pointed needles of the same mm size make the same stitches. Only the diameter matters for gauge.