What are the different yarn weights and how to convert between them October 16 2024, 0 Comments

Yarn weight refers to the thickness of yarn and is described in different ways in different countries. This means sometimes when you look at a pattern you might not recognize the term used. This table shows the common terms used in USA, UK and Australia to help you convert between them. It is shown alongside the meters per 100g and the WPI (wraps per inch) which are more quantitative measures of a yarn's thickness.

UK USA Australia m/100g WPI May also be called
Cobweb 0 or Lace 800+ 40+ 1 ply, Thread
Laceweight 0 or Lace 600 - 800 30 - 40 2 ply
3 ply, Light Fingering 1 or Super Fine 3 ply 500 - 600 20 - 30 Baby
4 ply, Fingering, Sock 1 or Super Fine 4 ply 350 - 450 14 - 24 Baby
Sport 2 or Fine 5 ply 250 - 350 12 - 18 5 ply, Baby
DK 3 or Light 8 ply 200 - 250 11 - 15 8 ply, Light Worsted
Aran 4 or Medium 10 or 12 ply 120 - 200 9 - 12 Worsted
Chunky 5 or Bulky 12 or 16 ply 100 - 130 6 - 8 Rug
Super Chunky 6 or Super Bulky and 7 or Jumbo Less than 100 Less than 6 Roving

 

You will see however that some names may refer to more than one weight and some of the length and WPI categories overlap so it isn't just about choosing a different yarn with the same weight name. This is when comparing the meters per 100g (if the fibre content is the same) or WPI can help choose a comparable yarn.

It is also important to swatch with the yarn you are planning on using to see if you can get the gauge specified in the pattern and its a fabric you like that is suitable for what you are making. Even if the pattern states a DK yarn if you are using a 11 WPI yarn when the designer used a 15 WPI yarn you may not reach gauge or if you do the fabric won't have the same drape.

I hope this will help you choose the right thickness yarn for your project.

If you would like to read more about the term ply and what it means, please have a look at this blog post I wrote a few years ago.