A Guide to Crochet Thread and Steel Hook Sizes

When it comes to selecting a crochet thread, all of us get stuck at is: What type of crochet hook do we need? And the next one is also obvious: What crochet hook size works with all the different sizes of crochet thread?

Well, to answer these questions, read on ahead, and this guide will help you choose the right size of steel crochet hook and crochet threads for any thread project. 

First of all, what are the crochet thread sizes? 

Basically, thread size is related to the thickness of the thread. Crochet threads come in many different sizes, ranging from 3 to size 100. Some crochet threads are as thick as yarn, while others are like an embroidery or needle thread. The main point to remember about crochet thread size is that the larger the number of the thread, the thinner the thread. 

To keep it simple – “Bigger is Smaller.”

For example, Size 3 is much larger than Size 30. Inversely, Size 10 is thinner than Size 8, and so on.

Crochet Thread Sizes: 3, 5, 8, 10, 20, 30, …, up to size 100

Another thing to note here is that the size of crochet thread balls varies. They have different yardage or meterage, and it is mentioned on the packaging. Different brands may have different yardage and weight of a crochet thread, say of size 10. For example, Aunt Lydia’s Crochet Thread Classic 10 has a length of 2730 yards, while Coats Crochet Red Heart Classic Size 10 is 1000 yards in length. 

Common Thread Sizes

These are some of the standard thread sizes that you can get from different brands such as Lizbeth, DMC, and others. But, not all brands make different thread sizes. Some might even have a different size numbering for different brands. Check out this table for a size comparison between different brands. 

Thread Size	Lizbeth	DMC Cordonnet	Pearl Cotton	Cebelia
Size 3	3		3
Size 10	10		5	10
Size 20	20	20	8	20
Size 40	40	40	12	30
Size 80	80	80

Size 3 and 5 – The crochet thread is similar in thickness to a lightweight yarn such as sport or fingering yarn. It is an ideal choice for making scarves, lace tops, baby dresses, and many more projects. Size 3 is slightly thicker than the size 5 thread. These two are the most convenient if you are just starting to learn thread crochet. 

Size 10 – A crochet thread of size 10 is thinner than most other yarns. Size 10 crochet thread is an excellent choice for making lace edgings, motifs, doilies, jewelry, coasters, etc.

Size 20 and 30 – It is a typical size thread for tatting projects mainly, but it is also common in several crochet projects. You can use this crochet thread for making projects such as motifs, doilies, and others. 

Size 40 – This crochet thread size is also very common in crocheting and tatting projects. You can make crochet projects such as lace edgings, snowflakes, jewelry, and more. 

Size 80 – Thread size 80 is the ‘true’ tatting thread and is very fine. Other threads are referred to as ‘crochet thread’ or ‘cotton thread.’ This is ideal for tatting projects such as bookmarks, jewelry, edging, etc. 

Crochet Thread Fibers

The most common fiber that is common for crochet threads is cotton. You will be able to find it anywhere. But, other types of threads are more difficult to find. Some of the options include nylon, acrylic, silk, and metallic. 

Crochet Thread Brands

If you are looking to working with cotton crochet thread, you will be able to find it much easily. Some of the brand options for crochet threads include the common ones like Aunt Lydia’s and Herrschner’s. DMC is another familiar and trusted brand. 

Red Heart also makes its own line of nylon thread. If you are looking for some unique thread fibers, you can also check out Etsy sellers. 

Now, what type of hook to use? 

When you are working with crochet, either yarn or thread, typically, you use a metal hook. While other types of hooks such as plastic or bamboo are available, metal is the most preferred option. 

But why metal hooks?

The main reason for working with metal hooks is that they don’t bend. They are stiffer and easier to use, especially when you are working with thinner threads. Plastic and bamboo hooks will bend easily and making them uncomfortable and difficult to work with. Metal hooks are stiffer and will not bend under pressure, even with thinner threads. 

Crochet Hook Size

Hooks for working with crochet threads are different from regular crochet hooks. Their sizes are much different. In metal hooks, the larger the number, the smaller the hook. It matches with the way thread sizes work – the larger the number, the smaller the size of thread. 

This numbering and sizing are different from how the yarn sizes work. When it comes to yarns and regular crochet hooks, the larger number, the larger hook, or yarn, respectively. 

If you are working with yarn, refer to Size Conversion Charts for Knitting Needles & Crochet Hooks.

So, a size 40 crochet thread is much thinner than a size 10. Similarly, a size 10 is smaller than size 8 or size 3. 

In similar lines, a size 12 (0.60mm) crochet steel hook is much smaller than a size 8 (1.5mm) steel hook. 

The smallest steel hook size is 0.60mm, and the largest hook is 19.00mm (yarn crochet hook). 

Read our detailed guide on Steel Crochet Hook Size Chart for more information.

It might feel confusing, but it’s easy to follow. Here’s a simple table that can help you out.

Crochet Thread Size, Steel Hook Size, and Ideal Projects

Thread Size	Project Type	US Size	Metric Size (mm)
3	Garments	1, 2, 3	1.5, 1.75, 2.0
5	Lacey scarves, bags	4, 5, 6	1.25, 1.5, 1.75
8	Decorative items like flowers		0.9, 0.95, 1.0
10	Versatile	5, 6, 7	1.5, 1.75
20	Lacey doilies	7, 8, 9	0.90, 1.00, 1.10, 1.25
30	Doilies, borders, and edging	8, 9, 10, 11, 12	0.75, 0.85, 0.90. 0.95
40	Tatting and lace edging	9, 10, 11, 12, 13	0.6, 0.65, 0.7
60		11, 12, 13, 14	0.75
80		13, 14	0.60
100		14	0.60

This ultimate guide on crochet thread size and corresponding steel hook size will help you choose the right combination for your thread crochet projects. Most patterns give detailed instructions and tell you about the required materials, but if you are working on something new, you can refer to this crochet thread and steel hook size guide.

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