Worsted, Aran and 10ply… Oh my!

As I have explored knitting and crochet online and with my local knitting group I have noticed that there is a vast array of terms used to describe the thickness of a yarn. This is super confusing for beginners and even confusing for experienced knitters & crocheters that are accustomed to the terms used in their own country. I would like to demystify some of this.

Yarn Weights

The first thing to note about yarn, is that the thickness is generally referred to as the weight. Beyond that, the terms used to reference the weight is different depending on the country you are in, and the brand of yarn you’re looking at.

Standard Yarn Weights

There is a standard yarn weight system published by the Craft Yarn Council. I’m not sure how standard all of it is (i.e., whether manufacturers adhere to these gauges), but it’s a good place to start. I have found it quite helpful.

The names in the standard yarn weight table at the time of writing is as follows. Take a look at the Craft Yarn Council website for extra information such as recommended gauges and needle sizes.

Yarn Weight Symbol & Category Names
Type of Yarns in Category	Fingering, 10-count crochet thread	Sock, Fingering, Baby	Sport, Baby	DK, Light Worsted	Worsted, Afghan, Aran	Chunky, Craft, Rug	Super Bulky, Roving	Jumbo, Roving

If you’ve browsed Red Heart yarns you might have noticed they use the 1-6 scale of yarn weights. The first time I saw that on their website I had no idea what was going on! I had never seen that scale before. If you’re in the same boat, now you know! And it actually makes a lot of sense… more sense than the other word-based ranges I think.

Many other yarn brands and websites use the other scales shown in the table above: lace, super fine, fine etc. Or they use a combination thereof, e.g., lace, sock, sport, DK, worsted, aran, and bulky. This scale makes some sense and I think a majority of crafters around the world will recognise it. Lace is self explanatory, as is sock. DK, or double knitting, is a legacy name from Britain: apparently fine yarn was the most common weight, so if you knitted 2 strands of that together you got DK yarn, which is arguably the most common weight used these days. The term worsted can actually mean two things, which I’ll mention a little later, and although this table has worsted and aran both under medium, aran tends to be slightly heavier than worsted in my experience.

Yarn Ply

Enter Australian yarn weight terms!

Info in this table is courtesy of Wikipedia.

I thought I’d leave in the German as I have a German friend in my knitting group, and also the metres per 100 grams is an interesting factor that is not in the standards table.

Yes, that’s right! In Australia we usually don’t usually use any of the fancy names and we refer to yarn weight in ply. This scale makes perfect sense to Australians, and probably to most Britons as well, but it doesn’t come without confusion.

As a noun ply can mean thickness (so that makes sense in this context), or it can mean layer (e.g., plywood is sheets of wood layered together), or it can mean strand (a 3-ply cord is a cord made up of 3 strands). As a measurement of yarn weight, only the first noun definition, thickness, makes sense because if you look closely at your yarn, very rarely is 8-ply made up of 8 strands.

The other context in which the term ply can be confusing is as a verb: it can mean to join together by twisting. So, you could have a 2-ply yarn that is a medium or bulky weight because it was spun thickly and two strands of the same, or different, yarns were twisted together. This language is a lot more common in the hand spinners community.

WPI

WPI is wraps per inch (not WIP, work in progress!). It’s a shame that more people don’t know about WPI because if we used it more widely I think there would be a much greater consistency among yarn weights and labels!

As it happens, crochet cotton tends to be labelled by WPI, which is why the finer cotton is labelled with larger numbers. It was such a revelation when someone finally told me this! I had been wondering and occasionally asking people about that for years; it wasn’t until I took a tatting class that it finally made sense!

WPI as a measurement of yarn weight is a bit like meters per 100g, in that the lighter/thinner the yarn, the higher the number will be. You can measure the WPI of a yarn by wrapping it around a pencil, or ruler, or piece of dowl, and measuring the number of times it wraps around the item in one inch (or in 2 inches divided by 2, if you want a more accurate count).

There is some variation among manufacturers and individuals as to which WPI goes with which yarn weight. There is going to be some margin of error depending on how tightly the measurer wraps the yarn and whether there is any stretch in the yarn etc. Although Craftsy, Knit Picks and Ravelry seem to essentially agree on the numbers below.

Yarn Weight Symbol & Category Names
WPI	35+	19-22	15-18	12-14	9-11	7-8	6-

Is your mind blown? Even if it is, I hope the world of yarn weights is making a bit more sense to you! Feel free to bookmark this post to refer back to these tables… I’m pretty sure I’m going to!