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Needle and hook sizes

Pick a size to see it in mm, US and UK.

Knitting needles

mm	US	UK
1.5	000	—No number
1.75	00	—No number
2	0	14
2.25	1	13
2.75	2	12
3	—No number	11
3.125	3	—No number
3.25	3	10
3.5	4	—No number
3.75	5	9
4	6	8
4.25	6	—No number
4.5	7	7
5	8	6
5.25	9	—No number
5.5	9	5
5.75	10	—No number
6	10	4
6.5	10 ½	3
7	—No number	2
8	11	0
9	13	—No number
10	15	—No number
12.5	17	—No number
12.75	17	—No number
15	19	—No number
19	35	—No number
25	50	—No number
35	70	—No number

Crochet hooks

mm	US
2.25	B-1
2.5	—No number
2.75	C-2
3.125	D
3.25	D-3
3.5	E-4
3.75	F-5
4	G-6
4.25	G
4.5	7
5	H-8
5.25	I
5.5	I-9
5.75	J
6	J-10
6.5	K-10 ½
7	—No number
8	L-11
9	M/N-13
10	N/P-15
11.5	P-16
12	—No number
15	P/Q
15.75	Q
16	Q
19	S
25	T/U/X
30	T/X

The Craft Yarn Council table gives no UK hook numbers.

Go by the millimeters: numbers vary between brands. A dash means no number for that size.

Sources

• mm and US numbers: Craft Yarn Council, Hooks & Needles, read 12 November 2026.
• UK needle numbers: KnitPro, Knitting Needle Sizes & Conversion Guide, kept only where Wikipedia (Knitting needle) gives the same number. Both read 12 November 2026. Left empty: 9 and 10 mm (the two disagree), 1.5 and 1.75 mm (not in KnitPro).

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