Knitting and crochet · reference

Knitting needle sizes

Look up knitting needle diameters in millimeters and their US size labels.

Use the diameter in millimeters to compare needles. US size labels can vary by manufacturer. A dash means no US label is listed in the Craft Yarn Council table; repeated labels reflect the source’s size ranges.

Knitting needle sizes
Metric diameter	US size
1.5 mm	000
1.75 mm	00
2 mm	0
2.25 mm	1
2.75 mm	2
3 mm	—
3.125 mm	3
3.25 mm	3
3.5 mm	4
3.75 mm	5
4 mm	6
4.25 mm	6
4.5 mm	7
5 mm	8
5.25 mm	9
5.5 mm	9
5.75 mm	10
6 mm	10
6.5 mm	10½
7 mm	—
8 mm	11
9 mm	13
10 mm	15
12.5 mm	17
12.75 mm	17
15 mm	19
19 mm	35
25 mm	50
35 mm	70

Source: Craft Yarn Council, Hooks & Needles. Checked October 27, 2026.

Start with the diameter

Use the millimeter marking on your needle or packaging when comparing sizes. US numbers are labels, and manufacturers do not always assign them to exactly the same diameter. This chart retains the metric entries in the Craft Yarn Council’s reference, including duplicate US labels and unassigned sizes.

Size is only the starting point

Your needle’s diameter and your stitch gauge describe different things. Check a swatch made with your chosen yarn and the stitch pattern you plan to use. The gauge calculator below can help you turn that swatch into stitches and rows over a measured span.

Needle length is a separate measurement

The millimeters in this chart describe diameter, not the length of a straight needle or a circular needle’s cable. Check your pattern for both the needle size and the type or length it calls for.

Where this comes from

Craft Yarn Council, Hooks & Needles, checked 2026-10-27

Everyday Measure · everydaymeasure.com/knitting-needle-sizes/