Converter

Knitting needle size converter

Pick a needle size in any system to see it in the others, or use the full chart below.

MetricUSOld UK

Your result

Same needle4 mmUS 6UK 8

Knitting needle size chart: metric, US and old UK
Metric	US	Old UK
1.5 mm	000	–
1.75 mm	00	–
2 mm	0	14
2.25 mm	1	13
2.5 mm	–	–
2.75 mm	2	12
3 mm	–	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	10½	3
7 mm	–	2
7.5 mm	–	1
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	–
35 mm	70	–

Metric (mm) is exact; US and UK numbers vary a little by maker. Today the UK uses metric sizes.

Knitting needle size chart: metric mm, US and old UK sizes — Knitting needle size chart: metric mm, US and old UK sizes. Free to print and save.

How to use it

Pick the size from your pattern in the column it uses: metric, US or old UK.
Read the same needle in the other systems.
Where there's no exact match, use the closest metric size and check your gauge.

Questions

What is a US size 8 needle in mm?

5 mm. US 6 is 4 mm, US 7 is 4.5 mm and US 10 is 6 mm.

Why do some sizes have no US number?

Metric sizes are more finely graded. 3 mm and 7 mm needles, for example, have no standard US size.

What are old UK needle sizes?

The UK numbered needles the other way round, so bigger numbers are thinner: UK 8 is 4 mm and UK 14 is 2 mm. Today UK patterns use millimeters.

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