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understanding crochet thread

If you’ve heard of thread crochet, you might wonder how it differs from “regular” crochet. In this video I talk about crochet thread. I explain how the sizing system works for thicknesses of crochet thread. A transcript of this video is available at the end of the post.

Most crochet thread in mercerized. Mercerization is a process that makes cotton thread shinier and stronger. Crochet thread is now available is so many different colors.

In a future video I’ll talk about the steel crochet hooks that are used for thread crochet.

If you’re looking for more great crochet info, check out my crochet cheat sheet.


One of my crochet students recently was asking me about thread crochet. Thread crochet is worked just like regular crochet, the same stitches often, but it’s worked with this fine cotton thread instead of with big, bulky yarn. If you’ve seen examples of thread crochet before, it might have been in these really delicate table cloths or fancy doilies. So I want to explain a little bit about the threat that’s used in thread crochet.

Almost all the thread on the market is made from cotton. And often, it’s mercerized cotton. And what that means when you have mercerized cotton, is it’s been chemically treated in a process. And that process makes it kind of shinier. It makes it stronger, and it makes it absorbed dye better, which is part of why you can get thread for crocheting in all different gorgeous colors and they’re even variegateds out there.

The sizing for thread is different than what we use for the sizing for yarn. So often with yarn you’ll hear people talk about like a worsted weight or a sport weight or a sock weight. With thread, the size designations are numbers. So this is a size 3 thread. And this is very, very fine and very delicate. But this is actually one of the larger, thicker threads available on the market.

So this is size 3. Size 5 is going to be thinner than size 3. So once again, we’ve got this nice cotton thread. It’s a little bit thinner, and this is referred to as a size 5. The most common thread you’ll find out there is a size 10. Size 10 is smaller than size 5. Meaning, it’s thinner. It’s not as thick. And it’s by far one of the most popular thicknesses of thread to use for thread crochet.

It is possible to get even thinner thread. You can go down to a size 80, which is the equivalent of like sewing thread, and I have seen crochet done with sewing thread, which is absolutely gorgeous and really impressive. But the main thing when you’re looking at crochet thread is remember, as the numbers get bigger, the thread gets thinner. So size 3 is bigger than size 5. That’s bigger than the size 10.

Also, a hint, if you go into your store, especially like a Big Box craft store, and you’re looking for crochet thread, check out the embroidery section and the cross stitch section as well. So like this size 5 thread that I have, this was not in the section with the crochet thread. This crochet thread was kept near the yarns, like your regular standard yarns. This was actually in the section with the embroidery and cross stitch and needlepoint stuff. And if you go to kind of your embroidery needlepoint sections, you can find some really awesome threads in cotton or silk to crochet with and make beautiful things with.