Your Guide To Decoding Weaving Yarn Sizes

Your Guide To Decoding Weaving Yarn Sizes

Let’s imagine a scenario. You are planning a project and you need to buy new yarn (yay!) As you start browsing through your favorite yarn website – you see a lot of different yarns that look like they could be great for your project. Great except that yarn sizes range from 40/2 to 8/4.


Looking at the weaving yarn sizes can feel like you are reading a secret code. What do those numbers actually mean?

Before we move on it is important to note that sizing can vary between different types of yarn. 8/4 cotton and 8/4 linen won’t actually be the same size.

That would make too much sense.

yarn size

First Number

The short of it is that the first number in your fraction is the gauge of the yarn. Just like wire – the larger the number = the thinner the yarn. This is the same no matter the material make up of the yarn (cotton, linen, wool, etc.)

If you’re like me, though, then you might have some questions.

For example: where does that number come from? It all has to do with how many yards per pound (ypp) your yarn is. (We’ll calculate ypp later)

The standards for yarn sizes were decided a long time ago when yarn was first being produced. Cotton, for example, is based off of a size 1 yarn being 840 ypp¹. This gives you an approximate amount of yardage you can expect on your cone or tube. This number is really helpful when planning your weaving.

In contrast to cotton – linen size 1 is 300 ypp¹. This is why an 8/4 cotton and 8/4 linen aren’t actually the same size. 8/4 linen actually ends up being a thicker yarn. Keep this in mind if you are using cotton for samples and linen for your final product.

Unfortunately, there is no direct translation. If you want to figure out similar yarn sizes in a different material than look at the ypp and find one that is equal or close to the yarn you are looking to replace. This information can usually be found where you purchased your yarn – especially if you purchased it online.

yarn size

Second Number

The second number of your yarn size fraction is simply the number of plies your yarn has. 

When fiber is first spun it is called a single. Singles are rarely used in weaving because they aren’t as strong and they tend to have a lot of “energy”. This means they don’t always behave the way you want them to. Sometimes they don’t compress as well or weave as straight. That doesn’t mean you can’t do it – but it will be harder. 

A plied yarn has 2 or more single yarns twisted together. Generally speaking more plies = greater strength. This is why these yarns are more likely to be used for high traffic weavings like rugs.

Most yarns sold for weaving have 2 or 4 plies, but you can sometimes find thicker yarns with more.

This all means that, for example, 8/2 cotton has 2 sets of size 8 yarn twisted together. Likewise 8/4 cotton has 4 sets of size 8 yarn twisted together.

And so on.

It’s also good to note that this sizing isn’t standard worldwide. If you are purchasing yarn from another country then keep in mind that in some countries the size and number of plies might be reversed.

In this case, 2/8 cotton purchased internationally might just be the same as 8/2 cotton purchased in the U.S.

yarn size

Calculating YPP

You can now take these numbers and do a little bit of math.

I’m sorry.

Let’s take 8/2 cotton for example:

First, you will want to take the ypp numbers for a single (840 ypp) and multiply it by the first number of your yarn size.

This would mean that size 8 cotton can be described as having approximately 6,720 yards per pound.

You’re not done yet though.

There’s a second half to that equation. You have to divide it by the number of plies.

The entire equation looks like this:

840 x 8 = 6,720

6,720/2 = 3,360

8/2 cotton has 3,360 ypp.


Let’s put that into action.

Say you have a standard 8/4 cotton with a ypp of 1,680 (840×8/4). If you are looking for a similar sized linen for your project then you would want an 8/2 linen or 1200 ypp (300×8/2). While they aren’t exactly the same, they should be close enough to weave up the similarly. That being said, samples are always your friend.

Need help planning your weaving project? Stuck trying to figure out how much yarn you need? What the h&^$ is WPI? Check out my e-book!

Why is this important?

Ok, so I’m going to be super honest with you right now. The math we just did? Yeah, that might not be super important to know when you are planning your project. I didn’t know that a pound of cotton size 1 is equal to 840 yards for years into my weaving career and I never had any big issues.

It’s cool to know though for us yarn nerds.

Luckily for all of us, when ordering online most yarn stores tell you the recommended sett range for that warp and the approximate yardage per cone/ tube/ skein. The yardage plays a role when planning the project so you know that you are purchasing the right amount of yarn for your specific project.

That being said – if that information isn’t provided or you can’t find it then you now have the equations to figure it out yourself!

A note on recommended sett: keep in mind that the recommended range is usually for a balanced plain weave so you might have to adjust accordingly. This is where samples once again become an incredibly important part of your studio practice.

So I guess the moral of today’s post is to always read the yarn description and that there is a lot more to know about yarn and yarn sizes than you probably ever imagined.

¹Held, Shirley E. Weaving: a Handbook of the Fiber Arts. Holt, Rinehart and Winston, 1978.


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Yarn Notebook – Organize Your Yarn Stash

Yarn Notebook – Organize Your Yarn Stash

One of the greatest lessons I have learned from having my own studio practice is that good organization can save you.

Now that might seem a bit dramatic – but really it is one of those things that I figured out the hard way.

Even if organization doesn’t come naturally to you (guilty) sometimes you just need to buckle down so you can get through it, because in the long run you will be thankful you did.

In case the title didn’t tip you off: today we’re talking about using a yarn notebook.

It may not be the most exciting part of your studio practice, but it might just be the most helpful.

If I didn’t force myself to keep track of my yarn – I’d run out of something and have no idea what size it was or where to buy more. This obviously could be detrimental if you are mid-project. It can also be a good way to keep your studio stocked with the yarn you use the most. The notebook is an easy and inexpensive way to get your studio together. Pretty much everything you need can be purchased in the office supply section of any store.

This post may contain affiliate links. If you purchase something through these links then I will receive a small commission that helps keep the blog going – at no extra cost to you! Please read our DISCLAIMER for more info. Thanks for the support!

Need help planning your weaving project? Stuck trying to figure out how much yarn you need? What the h&^$ is WPI? Check out my e-book!

What You Need:

3 – Ring Binder

Card Stock

Plastic Sheet Protectors

Stapler or Tape



yarn notebook

The Binder

I’m sure there are many different options for keeping track of your yarn, but I find the most effective way to be in a 3 – ring binder.

I began using these binders for art handouts and notes throughout my time at VCU. They were actually required for the class – but I found them so helpful in the long run that I required them of my students as well while I taught there.

These binders still to this day are a great resource for a lot of my fiber related information and notes. You could even use yours to hold other information beyond your yarn stash. Think about storing samples and their respective information or receipts from yarn and tool purchases in case you can deduct them come tax time. Really you can use this to keep track of anything pertinent to your own studio.

So here’s how I’ve set mine up:

Card stock is a really great option to use for your notebook because it’s heavy enough to hold up to all your yarn samples but thin enough not to be bulky.

I have set up each page as a different type of fiber – but you could divide your pages between retailer, warp sett, or size. Then each each fiber page is split up into the five categories that are most important to me, but you should do what makes the most sense to you.

Possible Categories To Include:



Price per lbs/ cone/ tube



Warp Sett



Number of Cones You Have On Hand

yarn notebook

Other Considerations

If you dye your own yarn then it is really important to take good notes. This will help to avoid inconsistencies between dye lots. It’s always a good idea to dye all the yarn you need for each project at one time, but sometimes you need to recreate it. I don’t know about you, but my memory isn’t that good.

You might even want a separate notebook dedicated to this if you dye a lot of yarn.

Think of your dye notebook as a not so tasty recipe book.

Your notebook could also really help you out if you plan on selling your work. Having a well organized account of how much you paid for your materials can be a lifesaver when pricing out a piece that is already made or one that is being commissioned. On that note, a kitchen scale can really help you out to weigh your cones before and after the piece is finished. Doing this helps to get a more accurate account of how much yarn you used and therefore how much to charge for materials.

Don’t let the set up deter you. Setting up your yarn notebook shouldn’t take too much time unless you have a ton of yarn. If that’s the case, I recommend the notebook even more to help keep you straight. Honestly, the hardest part is just remembering to update the notebook when you buy new yarn.

Speaking of…


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Pick The Right Warp For Your Next Weaving

Pick The Right Warp For Your Next Weaving

When you need to pick the right warp for your next project it isn’t as easy as just grabbing the first cone you can. It takes the right kind of yarn to be able to withstand the tension that the warp will be under. That’s not the only consideration though.

So how do you pick the right warp and what should you be looking for?

This post may contain affiliate links. If you purchase something through these links then I will receive a small commission that helps keep the blog going – at no extra cost to you! Please read our DISCLAIMER for more info. Thanks for the support!

First, let’s take a second to go over the difference between warp and weft. 

Your warp yarn is the foundation for your weaving. It is literally what you build upon – like the foundation of a house. The warp sits vertically in your frame or on your floor loom. 

Your weft yarn is the part of the weaving that turns it into a fabric. It interacts with the warp and sits horizontally. Remember: Weft Goes Left. If we are sticking with our construction metaphor – it’s the walls.

Weft can be ANYTHING!

I mean that.

You can weave with yarn, fabric, grass, hair, etc. If it’s long enough then you can use it as weft. 

Yes, I said hair.

When you need to pick the right warp on the other hand there are a few considerations you need to well… consider.





Size Matters  Yarn Size Matters


Well, it does.

The size of your yarn can help determine the EPI of your weaving. If you’re not sure about the importance of EPI – then make sure to check out THIS post. 

A thicker yarn will have a different EPI than a thinner yarn for the same kind of weaving. When it comes down to it – it’s all about the interaction between warp and weft. Thin and thick yarns interact, compress, and behave differently.

Some very common yarns to use for your tapestry warp are either 8/4 cotton, or 8/2 linen. With these size yarns you are able to weave a standard 6 EPI for tapestry with a lot of different weft yarns.

This is a great place to start. Just never forget to sample!

But… Let’s imagine just 2 out of the endless possibilities you could try:

You could choose a really thin yarn and set your warp up for tapestry to create a very intricate image. Think of image building in tapestry like pixels. The higher the EPI – the more pixels you have to work with.

Choose a really thick warp yarn to create wide warp channels. The warp channel within a weaving is created by the high compression of weft over the warp in tapestry. This is largely determined by the size of your warp. You could double your warp or use a thicker warp to create larger channels for a different look.

pick the right warp

Strength Under Pressure

If you take a piece of yarn that you want to use for your warp and put it under tension, it should take some strength for it to snap. Now I’ve never done it – but I would imagine that you can’t just go into a yarn store and start snapping yarn to test it’s strength.

I am not recommending you do this.

If you already own the yarn though then snap away! 

If your warp snaps after just a simple pull from you then either you will have to be very careful about the tension you put it under while weaving or be prepared to fix a lot of broken warps.

No one wants that.

Depending on how easily it breaks – it is possible to use it as warp for a more balanced weave that doesn’t require high tension. Play around with it and as always: SAMPLE FIRST!

So what if you do find yourself in a yarn store and you need to pick the right warp? After you resist the urge to break the yarn in your search for warp then you can look at the material to help you determine if it will work for you.

pick the right warp

Material – Plant, Animal, or Oil

Yarn material can be put into three general categories: cellulose, protein, and synthetic. Cellulose yarn is made from plants, protein from animal hair or fur, and synthetic yarns are man made from things like petroleum.

Some materials are just better for warp than others. For example, cotton and linen are generally stronger than alpaca. This has to do with the length of the fibers that are used to make up the yarn. The longer they are, the harder it is for them to come apart. That doesn’t mean you can’t use alpaca for warp – you just have to be more careful and you probably wouldn’t use it for tapestry.

Why would you want to use it for tapestry anyway? You would be hiding that beautiful alpaca yarn under your weft yarns!

Please don’t do it!

Cotton and linen are the preferred warp choices for tapestry.


They’re really strong and tapestries are under a higher tension than their pattern woven counterparts. They are also usually smooth and allow for the weft to glide over them effortlessly. This smooth texture helps to ensure the weft flows over the warp instead of being caught on it.

On the other hand, using a warp with a little bit of “tooth” to it like a wool or alpaca will help to keep your weft in place for a more balanced weave. Keeping your weft in place helps to maintain your ideal warp to weft ratio.

Need help planning your weaving project? Stuck trying to figure out how much yarn you need? What the h&^$ is WPI? Check out my e-book!

Another consideration is that cotton tends to be softer and linen more stiff (at least until you wash it a few times). Keep that in mind when choosing as well. How do you want your weaving to drape?

Do you want it to drape?

Protein fibers tend to drape better than cellulose (but not always). Also, un-mercerized yarns drape better than their mercerized counterparts.

Mercerization is a treatment applied to some cellulose yarns to help them take dye better. It also makes them shrink less and gives them a shiny appearance.

pick the right warp

Color – To dye or not to dye?

Color may or may not play a role in the warp you choose. A weft-faced weaving (tapestry) by definition is weft-faced. The warp is completely covered up by the weft.

There is a matter of the warp ends to deal with, but there are ways to finish a weaving where you can’t see the warp at all. Depending on your ideal finishing techniques you may want to consider a dyed warp. If you plan to finish your weaving with the warp completely hidden – then you can use the same warp for every weaving regardless of color.

On the other hand, a balanced or a pattern weave will show the warp. In this case the color is very important for the overall look of the weaving. You can either choose a warp color that is the same or similar to the weft so it blends into the overall weaving or an opposing color to make it really stand out.

It all depends on your goals.

When it comes to the color of your yarn you have the option to either purchase pre-dyed yarn or dye it yourself. Either way, it is important to know how much yarn you are going to need if a consistent color is your goal since color can vary between different dye lots. If you purchase a dyed yarn one day and the SAME yarn a week later – it may look different.

Same goes for dying your own. You’re only human and so many things can affect the resulting color of your dyed yarn that it is best to dye it all at once.

This is where planning comes into play.

If you have an unstable foundation – the rest of the house could fall. That’s why starting off with the right warp for your weaving is so important. 

Do you have a favorite warp yarn? Let me know!


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