Knitting needle sizes chart
US, UK and metric knitting needle sizes side by side, with the yarn weight each one usually pairs with.
Updated August 11, 2026·4 min read
Metric is the size that's real. US and UK numbers are conventions layered on top of it, and the UK scale runs backwards, so a UK 8 is thinner than a UK 4. Match on millimetres and you'll never convert wrong.
| Metric | US | UK | Common yarn weight |
|---|---|---|---|
| 2.0 mm | 0 | 14 | Lace |
| 2.25 mm | 1 | 13 | Lace / fingering |
| 2.75 mm | 2 | 12 | Fingering (sock) |
| 3.0 mm | — | 11 | Fingering |
| 3.25 mm | 3 | 10 | Fingering / sport |
| 3.5 mm | 4 | — | Sport |
| 3.75 mm | 5 | 9 | Sport / DK |
| 4.0 mm | 6 | 8 | DK |
| 4.5 mm | 7 | 7 | DK / worsted |
| 5.0 mm | 8 | 6 | Worsted |
| 5.5 mm | 9 | 5 | Worsted / aran |
| 6.0 mm | 10 | 4 | Aran |
| 6.5 mm | 10½ | 3 | Aran / bulky |
| 8.0 mm | 11 | 0 | Bulky |
| 9.0 mm | 13 | 00 | Bulky |
| 10.0 mm | 15 | 000 | Super bulky |
| 12.0 mm | 17 | — | Super bulky |
| 15.0 mm | 19 | — | Jumbo |
| 19.0 mm | 35 | — | Jumbo |
| 25.0 mm | 50 | — | Jumbo / arm knitting |
Yarn weight to needle size
This is the starting point, not the answer. The ball band overrides the chart, and your gauge swatch overrides the ball band.
| Weight | Category # | Needle range | Stockinette gauge, 4 in |
|---|---|---|---|
| Lace | 0 | 1.5–2.25 mm | 33–40 sts |
| Super fine / fingering | 1 | 2.25–3.25 mm | 27–32 sts |
| Fine / sport | 2 | 3.25–3.75 mm | 23–26 sts |
| Light / DK | 3 | 3.75–4.5 mm | 21–24 sts |
| Medium / worsted | 4 | 4.5–5.5 mm | 16–20 sts |
| Bulky | 5 | 5.5–8.0 mm | 12–15 sts |
| Super bulky | 6 | 8.0–12.75 mm | 7–11 sts |
| Jumbo | 7 | 12.75 mm and up | 6 sts and fewer |
How to actually pick a size
Cast on with the size the pattern lists, knit a swatch at least six inches wide, wash and dry it the way you'll wash the finished thing, then count stitches across four inches in the middle.
- Too many stitches in four inches means your gauge is tight. Go up a size.
- Too few stitches means it's loose. Go down a size.
- Row gauge is off but stitch gauge is right. Usually fine. Most patterns tell you to knit to a length, not a row count.
Two chart quirks worth knowing
- US sizes skip 12 and 14. After US 11 (8.0 mm) the scale goes to 13, then 15. Not a typo in your pattern.
- Vintage UK patterns can be off by a size. The old imperial gauge scale was standardised over time, so a 1960s pattern's needle number may not match a modern conversion. Trust the stated gauge over the stated needle.