The Ultimate Guide to Substitute Yarn [2022]

There are many reasons to substitute yarn in a pattern. Maybe the recommended yarn is no longer available, you’re allergic to its fiber contents or you just want to use a yarn you already have. You can substitute yarn… but not all yarns will work equally. This guide will help you determine how to substitute yarn when the need arises.

Hey there!

This guide was designed to help you determine the best possible yarn substitute for the pattern you have your eye on no matter the reason you want to substitute. We’ll look at how things like yarn weight, color and construction can all affect a project and how you should consider these things when looking for a substitute. We’ll answer commonly asked questions like “can I substitute DK yarn for worsted?” (that’s a no!) We’ll help you understand why a yarn was chosen for a project and how to pick a suitable substitute. And finally, we’ll give you a step-by-step framework for you to use the next time you have to substitute a yarn in a project.


  • It’s All About The Yarn
  • Yarn Weight Classification
  • Stitch Definition, Drape and Elasticity
  • Fiber Content
  • Yarn Construction
  • Yarn Coloration
  • When You Substitute Yarn, Check Your Gauge
  • When You Find The Right Substitute, How Much Do You Get?

With Yarn Substitution, It’s all about the yarn.

This should come as no surprise, really. The most important thing to consider when substituting a yarn is the original yarn itself. So it makes sense to start here, both in this guide and in your effort to substitute a yarn.

When a designer sets out to make a new pattern, choosing the yarn for that project isn’t as simple as picking something they like. They’ll consider things like weight, stitch definition, drape, elasticity, fiber content and yarn construction amongst a few other factors. Each of these inherent yarn qualities contributes to its behavior as a finished project and your experience working with it.

Suffice it to say, each of these things needs to be considered when searching for a good substitute. With your pattern in hand (that you want to substitute yarn for) let’s look at them one by one so you can zero in on the right substitute.

Yarn Weight Classification

If you’re no stranger to yarn, you’re probably familiar with yarn weight classifications. If this concept is still a little new to you, check out our essential guide to yarn weight before you try to find the best substitute. It’s a quick and easy read but the benefit you’ll get from the knowledge within, will be useful for you as a knitter or crocheter in more ways than substituting yarn!

What is the yarn weight classification of the pattern’s yarn recommendation? In some cases the pattern will have the CYC yarn weight symbol right there on the page but in most cases, the pattern will only list the brand and name of the yarn and you’ll have to figure this part out on your own.

Do a quick Google search for the yarn brand and name. This should bring up a few trusted sources like the yarn manufacturer’s website or a link to a popular craft store. In either case, following the link will lead you to the product description. Look for the yarn weight category symbol and write that down.

This is the single most important piece of information when substituting yarn.

Why is it so important you ask? Because if you substitute with a thicker or thinner yarn, the project won’t be the same size as the sample in the pattern. Sure you can potentially fudge it by manipulating the gauge (more on that later) but that’ll lead to a project that doesn’t look or feel the same.

Sizing and how the fabric “behaves” are the pillars of the project. If one is off, it can turn into a bad experience very quickly.

Step 1: Choose a Yarn in the Same Weight Category

Write down the CYC weight classification for the recommended yarn and choose a yarn in the same weight category. There, we said it again for emphasis because if you take only one thing from this guide, it should be this point. Only substitute with a yarn in the same weight category.

If you initially feel overwhelmed by the sheer volume of yarn options you could potentially sub with, this will drastically reduce the stress level (and number of options). If the sample yarn is a #4 medium weight, only entertain yarn possibilities in the medium weight category. If the sample yarn is a #2 fine weight, only look at options with the same weight symbol.

If you’re not sure about yarn weights or you’re confused by the different names sometimes used for them, our yarn weight guide will really help fill in the gaps.

But a lightweight yarn is so close to a medium weight yarn, can’t I just change the hook/needle size to make it work?

It seems simple enough, right? But honestly, this is the best way to make sure your substituted project starts off on the wrong foot. You can almost always find the right combo to match gauge across most yarn weight categories but this will always affect the fabric.

Let’s say your sample is worked in a medium weight yarn with a 5mm hook. You could theoretically use a #2 yarn and say a 6.5mm hook and get the same gauge but the fabric will be thinner and have more holes in it. Alternatively, you could choose a #5 yarn and say a 4.5mm hook and get the same gauge but that fabric will be stiffer and thicker. This will affect the project overall.

So err on the side of caution and heed our warnings. Choose a yarn in the same weight category as the sample.

Stitch Definition, Drape and Elasticity

Now that you know what yarn weight category you’re limited to, you can start looking at your best options. But first, you’ll need to consider the stitch definition, drape and elasticity of the sample. These important qualities of the project come directly from the yarn (and stitch pattern the designer chose too). They all describe the look and feel of the project as well as the effect and appearance of the fabric.

Stitch Definition – Take a look at the sample. Can you see the stitch pattern well or does the fuzziness of the yarn sort of conceal the pattern?

Stitch definition is the word used to describe how easy or how difficult it is to see the individual stitches in a piece of crochet or knitted fabric. Good stitch definition means you can clearly see each stitch while poor stitch definition means you can’t see the individual stitches and in most cases, can’t see the overall pattern.

This is often a design choice. You wouldn’t want to spend extra time on an intricate stitch pattern if the fuzziness of the yarn will hide your effort, right? That’s why it’s important to choose a substitute that matches the smoothness of the recommended yarn, because you want to match the stylistic look of the finished project with your substitute.

Drape – Take another look at the sample. How does it hang? Drape tends to collect in folds or waves. Does it have drape?

Drape is described as stitches which move freely against one another and is heavily influenced by the yarn fiber. Slippery fibers like many plant fiber yarns create drape because the stitches slide against each other easily. So if the project you’re subbing yarn for has drape, you may consider a plant based fiber (more on that later).

Yarn construction and the tightness of stitches also affect drape so you’ll want to study your pattern and recommended yarn well. Is it a plant fiber yarn like cotton? Is it a thinner yarn that uses a larger hook/needle? This wasn’t a happy accident. These qualities were designed into the project and you’ll likely notice if the substituted yarn doesn’t match the qualities of the recommended yarn.

Elasticity – Take yet another look at the sample. Does it have a tight fit (like a hat for example)? Does it have to stretch to put it on but shrink when in place like a sock?

Elasticity is the yarns ability to stretch and return to its original shape and is also a very important quality for certain projects like we saw with the hat and sock example above. If the project needs to stretch and return to a basic shape or if it needs to have a snug fit, you’ll need to choose a yarn with inherent elasticity.

Generally speaking, animal fiber yarns have the best elasticity with sheep’s wool being the most inherently elastic. Alternatively, plant fibers like cotton have no elasticity at all. So if your project needs to stretch, you won’t want to substitute with a cotton yarn. Inelastic yarns will allow the crocheted or knitted fabric to stretch and never return to their original shape. This can lead to a saggy disappointment.

Step 2: Take Notes On The Recommended Yarn

Specifically, what we just talked about. Is the yarn smooth? Does the project have nice drape? Does it need to stretch and return to its original shape? Write all these things down so you have them as a reference later.

Fiber Content

By this point, you’ve had a good look at the sample you’re substituting yarn for and hopefully you have notes on the yarn weight category and things like how it hangs or how it’s worn. The next thing to consider is the fiber content of the recommended yarn. It’s equally as important to understand how each fiber behaves as you’re working with it and in the finished project.

Like everything we’ve talked about so far, the yarn’s fiber content plays an important role in the design and was an intentional choice of the designer. So you too must make an intentional and educated choice when finding a substitute.

Animal Fiber Yarns

Animal fibers are seen as great insulators so they’re perfect for projects you want to be incredibly warm. As we mentioned above, they’re also inherently stretchy which makes them pleasant to work with and improve the tidiness of the finished project. Wool, alpaca, cashmere….there are many options. If your goal is to substitute with another animal fiber yarn, use the sample yarn as a guide. If it’s a wool yarn, it’s probably best to stick with another wool yarn.

But what if the reason you’re substituting yarn is because you’re allergic to animal fibers? It’s best to stick with a synthetic yarn with some inherent elasticity.

Plant Fiber Yarns

Plant fiber yarns like cotton, linen or silk are inelastic. So if elasticity is an important design element like in the case of a pair of socks, substituting with a plant fiber yarn is a bad choice. It will stretch, then sag. Plant fibers are made of cellulose which is responsible for their lack of flexibility. This quality, however, makes them great at releasing heat and keeping the wearer cool.

Synthetic Yarns

Synthetic yarns like acrylic, nylon and polyester are affordable choices that are pretty easy to get your hands on. They’re typically the easiest to launder and care for and are resistant to mold, mildew and pests. So why wouldn’t you use an acrylic yarn for everything? Well, they tend to pill easily with abrasion and wear, can be challenging to block and some synthetic yarns don’t exactly scream “quality”.

You’ll find some synthetic yarns to be inherently elastic depending on what they’re blended with so they can usually be substituted for an animal fiber yarn if the need arises.

Step 3: Determine the Right Fiber Content for Your Substitution

Take a good look at the yarn you want to substitute. Study the fiber content. Choosing a yarn with the same fiber content is the best first option. If that doesn’t work or you can’t because of an allergy, find a yarn with similar inherent qualities we talked about; insulator vs not insulator, elastic or inelastic.

Yarn Construction

This one might throw you for a loop but it’s equally as important to get right for the longevity of the project. Yarn construction is a term used to describe how the yarn is made and plays a big role in how a yarn wears over time. Not only that, the inherent qualities of fiber content can be amplified or downplayed with a yarn’s construction.

You’re probably very familiar with plied yarn. These yarns are made up of two or more individual strands that are twisted around each other. They’re stronger when compared to yarns with other construction methods and they’re less likely to pill or show intense signs of wear. They tend to have great stitch definition and more plies also means more density which can translate to more warmth for the wearer.

Equally as popular is roving or “singles” yarn. These yarns are very soft and lofty. They bring great texture to a project but usually at the cost of durability. Since they’re only held together with a single twist, they’re more likely to show wear and abrasion over time.

What about woven or knitted yarn? These yarns aren’t available in nearly as many options as plied or singles but you’ll find a few on your search for the right substitute. These yarns are spun threads that have been knit (icord) or woven into a tube or ribbon. Ribbon yarns don’t look uniform when worked up so keep that in mind if you’re tempted to sub with a ribbon yarn. Chainette (or those icord yarns) are different, however. They have great stitch definition and uniformity. They’re great insulators and have a lofty feel. As great as this all sounds, they’re still not as durable as plied yarns.

Don’t forget novelty yarns. This tends to be a catch all category and consist of yarns that don’t fit in any of the categories above. They are typically the hardest yarn to find a substitute for because many of them are purely unique. In most cases, you won’t find a good substitute for a novelty yarn.

Step 4: Choose a Yarn With The Same Construction

Since factors like the look and feel of the project, durability and longevity of the project are affected by a yarns construction, it’s best to choose a substitute yarn with the same construction as the sample yarn. This will make sure the project has the same look and feel as the sample.

Yarn Coloration

Although it doesn’t seem like a big deal, color is often a big factor in a pattern and should be heavily considered when making a yarn substitution. Take another look at the sample. Is a solid color used? Is a multicolor yarn used? If yes, how long or short are the color variations? Is an ombre or striping yarn used? No matter what the case may be, it’s typically best to stick with the same color qualities for your substitution.

Solid colored yarns with even color throughout are typically a design choice to allow the focus to be on the stitch pattern. So if the pattern you want to substitute yarn for uses a solid yarn and an intricate stitch pattern, it’s best to sub with another solid colored yarn. That way the effort you put into that stitch pattern can really be seen and admired. Another thing to consider that’s easily overlooked is how dark the yarn is. Back, dark gray, navy or any other dark colored yarn will make it harder overall to see the stitch pattern.

Multicolored yarns present more of a challenge for substitution because there are so many varieties. Not only that, it can be very difficult to visualize what a multicolored skein of yarn will look like worked up. Plus things like stitch pattern and gauge will affect how the coloration is presented in the finished fabric. If your sample yarn uses a multicolored yarn, see what that yarn looks like in skein form and try to determine how long each color is. Picking a substitute with a similar color transition length will make sure the substituted yarn gives a similar effect.

With self striping yarns, it’s best to consider the overall look of the stripes as they appear in the sample and find a yarn with the same color length. You’ll also want to consider how much of the sample relies on color and striping for it’s unique design, and do your best to match that with the substitute.

You may find this to be the most difficult part of the process. Finding a yarn with similar color characteristics can sometimes be a challenge. But there are a few key factors that’ll help:

  • The stitch complexity can be highlighted or hidden by color choices.
  • Color can detract or accentuate a project’s shape and design.
  • In some cases, the design depends on the presence of color or color variation

If you believe any of these to be true, you’ll want to spend a little extra time finding the right substitute. Be as strategic as possible and you’ll be happier with the project in the long run.

Step 5: Choose a Yarn With Similar Coloration

This is the final checkpoint so your options will be very narrowed at this point. Choose the option with coloration that’s as close to the recommended yarn as possible.

When You Substitute Yarn, Check Your Gauge.

At this point you’ve gone through all the options and selected what you think will be the best substitute. With the new substitute yarn in hand, you’ll have to put it through one more big test before you’re cleared to start the project.

Gauge is a way to measure the size of your stitches. If they measure the same amount as the sample gauge, the project will turn out the expected size. If not, it won’t. Even the slightest difference in gauge can make a big impact over the scale of the project. So it’s really important to get this part right, especially when substituting yarn (but it’s still important if you’re not substituting yarn).

You might be tempted to skip this step altogether, especially if you chose a yarn that’s in the exact same weight category. But don’t skip this step! It’s true yarn weight categories have a standard for roughly how many stitches per inch to expect, so it’s reasonable to think that if you use the same hook/needle size and the same weight yarn the gauge will match. But it won’t always match. And since gauge affects the sizing of the project and how you expect it to fit, it’s so important to get this part right. Even the tiniest difference like a half a stitch can lead to big sizing issues if you’re not careful.

Step 6: Make A Gauge Swatch

After you’ve gone through everything we’ve talked about so far…considered the yarn weight, color, fiber and construction and found a substitute you’re happy with, the next step is to make a gauge swatch. Start with the hook or needle size recommended in the pattern and make a swatch in the pattern described in the gauge that’s about 6″ x 6″. Measure how many stitches you have per inch and compare that to the gauge in the pattern. If it matches, you’re good to go. If not, you’ll need to adjust the hook or needle size and make another swatch until it matches.

In general, to change one whole stitch per inch, go up or down two hook/needle sizes (from one size to the next is roughly a half stitch per inch difference).

Gauge is one of those topics that’s crucial to your success as a knitter or crocheter and to be completely honest, it’s not the easiest concept to grasp. That’s why we spend a LOT of time talking about gauge in different mediums, from different perspectives…all in effort to help it sync in, not matter your learning style. We have a collection of resources to help you master gauge here.

When You Find The Right Substitute Yarn, How Much Do You Get?

Fortunately, the last piece of the puzzle here is also the easiest. You found a yarn you’re sure will make a good substitute because you took so many considerations to get there. Now how much do you get? Take another look at your pattern. Does it list the specific yardage required or does it simply list the number of skeins required to complete the project? If it lists the specific yardage, you’re safe to buy that amount of the substitute yarn (and if you really want to be safe, pick up one extra skein if you can). Easy peasy.

However, if the pattern only lists the number of skeins, you’ll have to do a little investigative work to see how many yards are in one skein of the recommended yarn. You can usually find this information on the manufacturer’s website, with a quick Google search. When you know how many yards are in a skein, multiply that number by the number of skeins the pattern calls for. That’ll tell you how many yards the project requires overall and how much of the substitute yarn you need to get.

For example, if a pattern calls for 10 skeins of yarn and each skein has 100 yards…

10 x 100 = 1,000

Ten skeins with 100 yards each, so you’ll need 1,000 yards of the substitute yarn.

If you’re feeling a little overwhelmed at this point, don’t worry. It’s not always easy to find the proper substitute, let alone feel confident in your decision. To help ease the self doubt, there really isn’t a right answer for the “what yarn to substitute for…fill in the blank”. There are only pros and cons and it’s your mission to find the best yarn that meets your needs.

Ask yourself the few basic questions we mentioned in this guide, take thorough notes and don’t rush or put too much pressure on yourself to find the “right” yarn. And most importantly, recognize that you’ll get better at all of this the more you practice substituting yarns in your patterns.

additional resources

3 Things You Must Do to Substitute Yarn on B.Hooked TV