How To Substitute Yarns in Knitting & Crochet

6 January 2021
Bookmark This (4)

Sponsored in part by:

Ad for the book Gathering Colour, featuring the book cover and the words, "Use natural pigments to make dyes, inks & paints from the world around you." A button at the bottom says, "Buy now."

There are many reasons to substitute a yarn when following a knitting, crochet or weaving pattern. Maybe the specified yarn isn’t for sale where you live, or it’s too expensive, or you’re allergic to its fibre content.

Substituting yarn involves more than simply finding a yarn of a similar weight. In this article, I cover many of the things you should consider, and why. I also provide some advice to designers and publishers to help them ensure that crafters can easily use yarns they love to make their patterns.

A Crochet or Knitting Pattern Should, At An Absolute Minimum, Include The Following

If a pattern you want to follow does not include the following information, it’s a major red flag. All of this information is key to your ability to choose appropriate materials to make the project, and if any of this is missing it may signal to you that the instructions may not be up to par.

Yarn Information

Yarn name and manufacturer (length per weight of ball/skein; fibre content); number of skeins required for each size; sample uses colour X.

Number of stitches and rows = 4 inches/10 cm in stockinette stitch.

For example, yarn information might look like this, for a knitting pattern that has three sizes:

Very Nice Yarn Companys Best Worsted Wool (220 yds/200 m per 4 oz/115 g; 50% Blue-Face Leicester, 50% Merino); 4 (5, 6) skeins; sample uses colour Beautiful Blue.

20 sts and 28 rows = 4 inches/10 cm in stockinette stitch.

Gauge information for a crochet pattern might look like this:

12 sts and 9 rows = 4 inches/10 cm in double crochet.

A pattern is simply incomplete without this information. All of this information. Even if you’re not going to buy the specified yarn, the information is a good guide. You can calculate the total estimated yardage required by multiplying the yardage per skein by the number of skeins needed for the size you’ll make. And the fibre content is an obvious guide for shopping.

Dearest Designer:

Provide complete yarn and gauge information. The better the information you give, the higher the chance a crafter has of being successful following your pattern – and the happier they will be with you and your work!

Dearest Crafter:

If a pattern doesn’t provide all the information I’ve listed above, consider choosing another pattern. It’s missing crucial information that you need to be successful, and who knows what else the pattern might be lacking.

Yes, Gauge Is a Tool for Yarn Substitution

The gauge tells you what weight”/thickness/category of yarn youre looking for; the number of stitches and rows that fits in a certain area of fabric indicates the thickness of the yarn

For a knitting pattern, Im talking here specifically about the stockinette stitch gauge. For crochet, single crochet stitch gauge should be provided.

Another indicator of the weight of a yarn is wraps per inch (WPI). This conveys the number of times the yarn can be wrapped around a ruler within one inch. This is also a variable measure, as the tension the yarn is under when wrapped influences the number of wraps that will fit in an inch. Ideally, WPI is measured with relaxed yarn, but we all know humans are inconsistent about such things.

At any rate, even if the project is worked in an all-over pattern stitch involving lace, cables, seed stitch, ribbing, whatever, the stockinette stitch/single crochet gauge helps indicate the thickness or “weight” of yarn you should use.

There are lots of yarns that are called “worsted weight,” but theres a lot of variance in how thick each is, and how each knits up. Same for fingering, DK, etc. A yarn weight name is a category, its not precise enough on its own to inform appropriate yarn selection. (And those category numbers? Same thing – they get you in the right section of the yarn shop, thats it! Theyre ranges.) The stockinette gauge is whats used on the yarn label, so thats how you can identify more precisely what to buy.

And of course, if the item is worked in an all-over pattern stitch – lace, cables, seed stitch, ribbing, whatever – a pattern should also provide the pattern stitch gauge.

Dearest Designer:

Please add stockinette stitch or single crochet gauge to all of your patterns. If a design features an all-over pattern stitch, or the pattern stitch uses a needle or hook size that’s different than the usual for that yarn, it’s worth making a note that you don’t necessarily expect crafters to swatch in stockinette stitch, but it’s helpful to say something to the effect of, “This pattern uses a yarn that typically works to x sts/y rows in 10 cm/4 inches using size z needles/hook.”

Dearest Crafter:

Use the stockinette stitch or single crochet gauge to identify the weight of yarn to use, and use the pattern stitch gauge to identify the needles or hook you need (to match gauge).

On Tool Size

You might have noticed that needle or hook size is not listed in the gauge example I gave. This might surprise you, but this information is actually optional. We include it by habit, but theres a risk that we make it seem like the tool size listed is sacred. The tool size listed in the pattern is simply a recommendation. Most of the time, its just the size the designer used to achieve the listed gauge. You may well need a different size to work to that gauge. (This, by the way, is what swatching is all about: making sure you use the tool thats right for you.)

Obviously, if theres more than one tool size used in a pattern – for example, one for the ribbing and one for the body of a sweater – then the gauge should specify which of the sizes is required, which might lead to a listing like:

20 sts and 28 rows = 10 cm/4 inches in stockinette stitch using larger needles.


12 sts and 11 rows = 10 cm/4 inches in single crochet using larger hook.

If the tool size is listed in a pattern, use that as a starting point for your swatching (unless, of course, you know that you’re habitually a looser or tighter stitcher, in which case adjust accordingly). And don’t be dismayed if you need a different size to get the same gauge – no two crafters work exactly alike.

Additional Yarn Information

Designers can help knitters a lot by adding a sentence or two to their patterns about why they chose a particular fibre/yarn/texture/colouring. This isnt an ad for a particular yarn brand or type, this is to communicate how the properties of the yarn used work in the project, and what characteristics are important if seeking a substitution. This can be simple, or complicated, depending on how much the design relies on those key characteristics.

For example:

  • Make sure youre choosing something that feels good on the skin, and is easy-care for this baby sweater; it should be safe for both machine wash and dry.”
  • This top is designed for hot weather: look for linen or hemp or other fibres that breathe. The slight stiffness of those fibers enhances the a-line shape.”
  • This design uses stranded colourwork. It looks best if you choose a sticky yarn with elasticity, so the fabric can be smoothed with blocking. A rustic (woolen-spun) wool or wool blend is best.”
  • This two-colour brioche project works best when worked with a solid colour and a variegated yarn that are highly contrasting; a variegated yarn thats too close to the solid isnt as effective, as the patterning wont be visible.”
  • The fine and detailed patterning in this openwork lace shawl looks best if worked in a solid or semi-solid colourway. It benefits from a good stretch when blocking, so a yarn that has elasticity and memory is best – choose a wool or silk yarn, or a blend of the two.”

Dearest Designer:

Uncertain about what to include in the Pattern Romance – the introduction? Here you go!

Dearest Crafter:

If this kind of information isnt provided, Google or your local yarn store can be your friend – find the yarn suggested and use that as a guide for finding a substitute.

On Yardage Estimates

Crafters have told me that instead of

x (x, x, x, x, … ) skeins

they prefer to see numbers for yardage, like:

1000 (1250, 1500, 1750, … ) yards (or metres).

Yardage has traditionally been indicated by listing the number of balls/skeins of yarn required because knitting and crochet patterns were often published by yarn companies. So of course theyd tell you how many balls or skeins of their yarn to buy!

Designers and publishers have stuck with this practice for a couple of reasons. They do it because its always been done that way, and they do it because yardage estimates are exactly that: estimates.

Let me be clear about how we go about determining yardage requirements for a pattern. As a designer, I weigh the finished sample and the swatch and determine how much yarn I used to create that sample. That one is easy. Then for the other sizes, I figure out how much bigger or smaller they are, compared to the sample I knit. Many designers use square inches, I tend to use total stitch counts.If the next size up from my sample is 10% bigger, then I need about 10% more yarn.

Then I round up – usually by 10-15% – to allow for swatching and other sundry things. And then I round that to full skeins.

I cant speak for all designers, but I do know that my process does give me an actual number for each size – but that number is an estimate. Expressing it as a number of skeins better communicates – I think – the inexact nature of these requirements. If I tell you that size M requires 1050 yards, but it turns out to need 1055? Thats potentially a big disappointment, a big problem.

There are situations where listing the number of full skeins isn’t ideal, and additional supporting information is helpful. The key one is where a project uses only a small fraction of a skein, as in colourwork projects, small projects worked in yarn that comes in very large skeins, and projects that only use a small bit of the final skein called for.

Dearest Designer:

Consider adding more specific yardage information, especially in the situations listed above. It’s up to you if you do it by listing specific yardages for each size, or just number of balls/skeins. If you’re doing it by balls/skeins, just make sure that you’re including yardage per ball/skein so that knitter can do the calculation.

Dearest Crafter:

Please remember that all yardage requirements are estimates. Make sure you have a little extra, to allow for a second swatch, or the cat chewing the end of one of the balls, or knots that you have to cut off, or alterations, or gauge or style variations. Did you know that two crafters can create a piece of fabric the same size and at the same gauge but use different amounts of yarn? If you’re using a finer yarn, you need a little bit more to travel the full path of a stitch. And if you use the same yarn and match stitch gauge but not row/round gauge, your yardage usage will be different, too.


Featured photo credit Les Triconautes on Unsplash.
Copyright © Kate Atherley except as indicated.

About Kate Atherley

Kate Atherley (she/her) is a co-founder, editor and publisher at Digits & Threads and Nine Ten Publications. She has worked in the crafts industry in one way or another since 2002 as a designer, editor, writer, and instructor. She's authored eight books about knitting, from a next-steps guide for newbie knitters to the industry's only guide to professional knitting pattern writing. Kate lives in Toronto, Ontario, with her husband and their rescue dog Winnie.

Related Posts

Large Blanket, Small Loom: Rigid Heddle Blanket Project

Large Blanket, Small Loom: Rigid Heddle Blanket Project

Can you make a blanket on a small loom? You bet! In this tutorial for readers with some experience weaving on a rigid heddle loom, learn how to make a big, beautiful, lightweight blanket by sewing three panels together (or just make one panel for a shawl!).

Weaving Techniques: Hemstitch Tutorial

Weaving Techniques: Hemstitch Tutorial

Like many crafters, weavers need to pay special attention to the beginnings and endings of their projects. By hemstitching the ends of your woven work, you secure the warp and weft threads and prevent unraveling. Bookmark this step-by-step tutorial so you can keep it handy!

How To: Tablet Weaving with a Twist

How To: Tablet Weaving with a Twist

This beginner-friendly introduction to tablet weaving features a warped-in method that encourages newer weavers to explore their creativity—by giving classic patterns a colourful twist!

Get 10% off!

Join our mailing list to get special Studio Membership pricing! PLUS hear about new Digits & Threads content and community news.

Subscription success! Well done, you.