Crochet Hook Sizes Chart

The reference guide you need to recognize and memorize crochet hook sizes.

Have you noticed a number, letter, metric value (or all three) stamped on your crochet hook? These values are used by manufacturers to identify the hook size, and the letter/number sizing can vary from company to company. Talk about confusing.

Millimeter sizing is the most accurate of crochet hook sizes because it’s a direct measurement.

Here at B.Hooked, you’ll find millimeter sizes in all our patterns, but sometimes you’ll encounter only a letter/number used in patterns from other sources. You’ll want to find the millimeter equivalent before you start.

That’s where this crochet hook size chart comes in handy. Memorize it or bookmark it, whichever you choose, to familiarize yourself with crochet hook sizes in both US and metric terms.

Millimeter SizeUS Size
2.25 mmB-1
2.75 mmC-2
3.25 mmD-3
3.50 mmE-4
3.75 mmF-5
4.00 mmG-6
4.50 mm7
5.00 mmH-8
5.50 mmI-9
6.00 mmJ-10
6.50 mmK-10 1/2
7 mm
8 mm L-11
9 mmM/N-13
10 mmN/P-15
15 mmP/Q
16 mmQ
19 mmS
25 mmT/U/X
30 mmT/X
For more information or for additional sizes, check out the hooks and needles standards from the Craft Yarn Council.
additional resources

Learning Guides from B.Hooked