Need help understanding fiber sizes

I've been working with threads and fibers for many years, but am new to weaving (rigid heddle) yarns and names.  I am having problems understanding and interpreting yarn names/weights.  Worst of all, I can't figure out how to look for the info in books, etc.  For example: in an "8/2 cotton", what does the "8/2" mean?  Does anyone know of a good book that might have reference info like this?  THANKS?


Posted on Wed, 12/18/2013 - 15:16


Don't worry you are not alone. Yarn count is not intuitive and I often go back to my notes to make sure I am remembering correctly. There are a lot of different ways to measure yarn size. I keep a list of the common systems in my notebook to reference when I'm shopping.

Cotton has it's own special measuring system. The numbers refer to the weight/ply. The first number indicates the size of the individual strands. The second number tells you how many plies make up the yarn.

The weight/size of cotton yarn is measured by the number of 840 yard hanks make up a pound. So with your example 8 hanks of 840 yards each would make up one pound. Or 6720 yards of single ply would weigh a pound. Since the yarn is 8/2 you have 2 strands making up the actual yarn so there would be 3360 yards in one pound.

This was very hard for me to understand at first. In fact it took me several years to understand cotton yarn count system.

Most other systems are much easier. 

I believe the Big Book of Weaving discusses this, but I'm not at home in my library. There is also a scan of a manual which discusses yarn count here

Let us know what other questions you have,


Posted on Wed, 12/18/2013 - 15:19

Copied from another:

I asked the same thing of a weaver friend of mine. I'll be quoting from Rachel Brown'sThe Weaving, Spinning, and Dyeing Book, ed.1987.

"These are numbers by which yarn size and ply are described.... Cotton, linen, woolen, and worsted yarns can all be described by count. #1 describes the size of the yarn that will be produced when spinning a certain base yardage from 1 pound of fiber.... For cotton, No. 1 is the size thread that results from spinning 840 yards from 1 pound of cotton fiber#2 would be the size thread if twice this yardage (1,680 yards) was spun from 1 pound of cotton... #10 would be a thread 8,400 yds long weighing 1 pound. So the higher the number, the finer the thread. This is single-ply thread.... When the thread is plied, the number of plies is given along with the thread size, as 10/2 (2 plies of #10 thread) or 6/3 (3 plies of #6 thread). The first number is the size of the thread and the second number tells how many threads of this size there are in the final plied yarn.

So, in a nutshell, your #8 thread is not as fine as #10.

Posted on Thu, 12/19/2013 - 05:08

Your answers were great!  I get it now.  So I have one more question: is Perle Cotton different because of its finish?  It has different weightng system, I think although it does follow "the larger the number, the smaller the thread".  Also, I will check out the book!

I live where most of my weaving supplies have to be mail-ordered, so it is important I understand what I am getting.  Thanks, again. Namaste

Posted on Thu, 12/19/2013 - 08:26

Weavolution was founded to bring the far flung weaving community closer together! I think many of us live quite far from other weavers. I'm fortunate enough to live near Cambridge, which has a very active Guild. I still love the regular interaction I have with others who live farther away.

I love that we have a place where we can all get together. I think this and other online resources help bring the weaving community back together. Early weavers had a large community tp learn from, as many people had to be involved in producing cloth for the community. I'm glad we are able to provide a way for use to rejuvinate the weaving community the way we are all rejuvinating hand weaving!

Posted on Thu, 12/26/2013 - 20:27

Perle (mercerized) cotton has the same numbering system as unmercerized cotton. Most retailers will also give the number of yards per pound. Here is a converter that will give you more units than you could ever want:

For cotton count you would divide the count by the number of plies, and then select "Cotton (English)" in the "select units" box. You can figure yd/lb by taking the resulting value in "Typp" and multiplying by 1,000.