REFERENCE CHART
Knitting needle size chart: US, UK and metric
Patterns from different countries name needles differently. Millimeters are the one size that means the same thing everywhere, so when in doubt, match the mm.
Needle size conversion chart
| Metric | US | UK / Canada |
|---|---|---|
| 1.5 mm | 000 | – |
| 1.75 mm | 00 | – |
| 2 mm | 0 | 14 |
| 2.25 mm | 1 | 13 |
| 2.5 mm | 1.5 | – |
| 2.75 mm | 2 | 12 |
| 3 mm | 2.5 | 11 |
| 3.25 mm | 3 | 10 |
| 3.5 mm | 4 | – |
| 3.75 mm | 5 | 9 |
| 4 mm | 6 | 8 |
| 4.5 mm | 7 | 7 |
| 5 mm | 8 | 6 |
| 5.5 mm | 9 | 5 |
| 6 mm | 10 | 4 |
| 6.5 mm | 10.5 | 3 |
| 7 mm | – | 2 |
| 8 mm | 11 | 0 |
| 9 mm | 13 | 00 |
| 10 mm | 15 | 000 |
| 12.75 mm | 17 | – |
| 15 mm | 19 | – |
| 19 mm | 35 | – |
| 25 mm | 50 | – |
A dash means that system has no common size there. Sizes are the ones CozyKnit offers when you add needles to a project.
Three things that trip people up
- Old UK sizes run backwards. A bigger UK number is a smaller needle. UK 14 is 2 mm, and UK 000 is 10 mm.
- US 2 and US 2.5 are close. US 2 is 2.75 mm and US 2.5 is 3 mm, and some brands label 3 mm needles as US 2.5 or don’t sell them at all. Check the mm stamped on the needle.
- Not every metric size has a US number. 7 mm, for example, sits between US 10.5 and US 11 with no US name of its own.
Your gauge decides, not the label
The needle size in a pattern is a starting point. If your swatch has more stitches per 4 inches (10 cm) than the pattern, go up a size. If it has fewer, go down a size. Then swatch again.
For which needles suit which yarn, see the yarn weight chart.