Crochet Hook Sizes | US and Metric Conversion Chart

Are you learning to crochet? Different crochet hook sizes can be confusing if you’re new to the craft. How do you know which hook to use with different types of yarn? And there are even different names for the same crochet hook sizes in Europe and the USA too!

Crochet hooks come in a range of sizes, and the size of hook needed is directly related to the thickness of yarn being used. A fine yarn requires a small hook, while a thick yarn will need a much chunkier hook. There are two main sizing schemes for crochet hooks: the metric system and the American system. The chart below lists the sizes available, with conversions for both systems:

crochet hook sizesCrochet Hook Sizes Conversion Chart

Metric Sizes American Sizes
2.00mm B1
2.25mm B1
2.50mm C2
2.75mm C2
3.00mm D3
3.25mm D3
3.50mm E4
3.75mm F5
4.00mm G6
4.50mm 7
5.00mm H8
5.50mm I9
6.00mm J10
6.50mm K10½
8.00mm L11
9.00mm M/N13
10.00mm N/P15
12.00mm O16
15.00mm P/Q
16.00mm Q
19.00mm S

Crochet hooks can be made from a variety of materials, including metal, plastic, wood and bamboo. Check out our great range of crochet hooks and experiment with different crochet hook sizes! Then let us know what you’ve been making!

Have you used all of these crochet hook sizes? Do you prefer working with fine or chunky yarn? Leave a comment below or post your thoughts on our Facebook page!

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