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Need help with crochet thread sizes

Dear All,

am asking for help, because I live abroad, and need to understand what exactly You mean under cotton thread sizes. I am trying to figure out the thickness of crochet cotton threads. There are sizes 3, 5, 10 to 100, but I can't find the information what the ratio of weight to length for each size of the thread is. Maybe anyone has an idea where I can get this info? Or at least the data how to convert these sizes in "tex" measurement unit?

Thank You very much in advance.


Have you done a Google search? There are a lot of thread merchants and most of them have size information. I don't know if any supply a ratio, but they may.

US threads are numbered from coarsest to finest. #3 and #5 are fairly thick and can be used with a large steel or small aluminum hook. #10 is the most commonly available and is used for everything from clothing to to potholders, to novelties, to lace. It is also what is meant by "bedspread" cotton in old patterns because it is sturdy. Medium steel hooks work well with this. While doilies are often made with #10, many lace makers prefer #20 or #30 for finer work. The very fine threads (#50, #70, #100) are often called "tatting" thread and are used by tatters and by crocheters using very small hooks. #100 is extremely fine. Hope this helps.

You might want to pick up samples. That would be the best way to determine for yourself what would suit your purposes.

I don't know if I can answer all your questions but here is what I know about thread sizes. The largest thread size is #3. It is somewhere betrween a sport weight and fingering/sock weight yarn in thickness. The next size is #5 which is half the thickness of #3. and it continues that way, getting thinner and thinner. I have never heard of weight to length ratios or "tex" measurement units.