Crochet Hook Size Chart (Printable): US Letters and mm

Crochet hook sizes in the US come two ways: in millimeters, and with a letter and number such as H-8. The chart below lists both.

The sizes come from the Craft Yarn Council’s hook size chart, and the hook range for each yarn weight comes from its yarn weight system. The Council represents leading yarn companies and advises going by the millimeter size, because letter and number sizes vary from company to company. We checked both pages in October 2026.

Crochet hook sizes in millimeters and US letters

Millimeters	US size
2.25 mm	B-1
2.5 mm	None listed
2.75 mm	C-2
3.125 mm	D
3.25 mm	D-3
3.5 mm	E-4
3.75 mm	F-5
4 mm	G-6
4.25 mm	G
4.5 mm	7
5 mm	H-8
5.25 mm	I
5.5 mm	I-9
5.75 mm	J
6 mm	J-10
6.5 mm	K-10½
7 mm	None listed
8 mm	L-11
9 mm	M/N-13
10 mm	N/P-15
11.5 mm	P-16
12 mm	None listed
15 mm	P/Q
15.75 mm	Q
16 mm	Q
19 mm	S
25 mm	T/U/X
30 mm	T/X

Some letters appear twice, such as G at 4 mm and at 4.25 mm. The Craft Yarn Council says letter and number sizes vary from company to company, so when a pattern gives both a letter and a millimeter size, go by the millimeters.

Steel hooks, used with crochet thread and lace yarn, are numbered in reverse of regular hooks: the higher the number, the smaller the hook. The smallest is a #14, at 0.9 mm, and the largest a 00, at 2.7 mm.

Printable crochet hook size chart

Save this chart to your phone, or print it and keep it with your hooks. It lists the common sizes from 2.25 to 30 mm.

Which crochet hook size for which yarn

The Craft Yarn Council’s chart numbers yarn weights from 0, the finest, to 7, the thickest. Labels that follow its system show that number inside a ball-of-yarn symbol. If your pattern names a hook size, start with that one and check your gauge with a swatch.

Yarn weight	Yarn types	Hook size
0 Lace	Fingering, 10-count crochet thread	Steel 1.4 to 1.6 mm (steel 6, 7 or 8), or a regular 2.25 mm (B-1)
1 Super fine	Sock, fingering, baby	2.25 to 3.5 mm (B-1 to E-4)
2 Fine	Sport, baby	3.5 to 4.5 mm (E-4 to 7)
3 Light	DK, light worsted	4.5 to 5.5 mm (7 to I-9)
4 Medium	Worsted, afghan, Aran	5.5 to 6.5 mm (I-9 to K-10½)
5 Bulky	Chunky, craft, rug	6.5 to 9 mm (K-10½ to M-13)
6 Super bulky	Super bulky, roving	9 to 15 mm (M-13 to Q)
7 Jumbo	Jumbo, roving	15 mm and up (Q and up)

The Council marks these ranges as guidelines only: they’re the hook sizes most often used with each weight. Make a gauge swatch and compare it with the gauge in your pattern. If your swatch is larger than the pattern’s gauge, use a smaller hook; if it’s smaller, use a larger one.

What size crochet hook for chunky yarn

Chunky yarn is weight 5, bulky, and its usual hook range is 6.5 to 9 mm, US K-10½ to M-13. Super bulky yarn, weight 6, takes 9 to 15 mm, US M-13 to Q, and jumbo yarn, weight 7, takes 15 mm or more.

Our Counting Crochet Hook Set has tips for both bulky and super bulky yarn: metal tips in 6.5, 7 and 8 mm, and 6 clear tips from 9 to 14 mm. The clear tips light up, which makes the stitches easier to see in dark yarn.

The 18 sizes in our Counting Crochet Hook Set

The LineaCraft Counting Crochet Hook Set has 18 tips from 2.0 to 14.0 mm that twist onto one handle. Here’s where each one sits on the chart:

• Metal tips: 2.0, 2.5 and 3.0 mm, 3.5 mm (E-4), 4.0 mm (G-6), 4.5 mm (US 7), 5.0 mm (H-8), 5.5 mm (I-9), 6.0 mm (J-10), 6.5 mm (K-10½), 7.0 mm, and 8.0 mm (L-11).
• Clear tips for bulky and super bulky yarn, the ones that light up: 9.0 mm (M/N-13), 10.0 mm (N/P-15), and 11.0, 12.0, 13.0 and 14.0 mm.

In the Craft Yarn Council chart, 9 of our 18 sizes have a letter. The 4.5 mm tip is US 7, a number only. The chart lists 2.5, 7 and 12 mm with no US size and has no row for 2.0, 3.0, 11, 13 or 14 mm, so go by the millimeters for those.

Whichever tip is on, the handle counts your stitches and rows and keeps the count when it switches off. Our guide on how to use a counting crochet hook shows how, and our guide to ergonomic crochet hooks covers choosing a comfortable handle.