How to Substitute Yarn

We've all been there: you finally find the perfect pattern, and want recreate the project right on down to the exact yarn shown. But then tragedy strikes: the yarn is out of stock (or prohibitively expensive). Don't worry! You can still make your knit dream come true. It's just a matter of knowing how to make a smart swap.

When I first started knitting, yarn substitution ruined many a project. I had no idea what I was doing. What should have been a warm, woolly hat suddenly turn into a floppy, drafty nightmare when knit it with a linen yarn. Legwarmers knit with an improper gauge came out big enough for two legs at once. And knitting vintage patterns with yarns unheard of since the 1960s? Those didn't turn out well...

Making substitutions still has the potential to trip me up, but I’m much more confident about my choices these days. As with anything else in knitting, you can learn from every substitution success and failure. And bonus for you: I'm sharing what I've already learned right here!

Yarn gauge and weight

The first thing I do when browsing for substitutes is to take a look at yarns in the same weight category as the pattern’s yarn. For example, if the pattern is knit with a bulky-weight yarn , I start my search in that weight category.

Then I consider the pattern's gauge: does the suggested gauge for my new yarn match the pattern gauge? Of course, this isn't a foolproof method, and there are ways to make an imperfect match work. If you change your needle size, you could potentially achieve the same gauge as the pattern and everything will be just fine.

Use the weight category as a starting point. If you can’t find anything you like, move to another category and try your luck by testing the gauge.


Do you want your substitute yarn to feel exactly as the original yarn does? If so, you should use a similar fiber.

The most obvious example of this is wool. You’re working on a sweater that’s going to keep you warm through the winter, but you need to substitute the yarn. The original sweater is knitted with a superwash merino wool yarn . Can you substitute a cotton yarn? You could, but you wouldn’t be nearly as warm as you would be in that wool! Think about the purpose of your project and what you’ll use it for. That will help you determine whether you should match the fiber exactly, or if you can go in another direction.

Fiber not only applies to something like warmth; it also applies to drape. Remember that yarns like cotton won’t stretch as easily as yarns like wool, so the final project may fit or hang differently.

Some yarns are a little stiffer than others, too. The shawl that drapes so beautifully on the model may not drape as well on you if you don’t use a similar fiber.


Don’t forget that the substitute yarn and the pattern yarn are probably sold in different yardages. Once you find your substitute, you’ll need to calculate the yardage to make sure you’re buying enough yarn.

The most accurate way to figure out how much yardage you’ll need is to check out the yardage of the pattern yarn. If the pattern yarn requires 4 skeins of yarn and each skein contains 130 yards of yarn, multiply 4 skeins x 130 yards to get 544 yards. That’s the total amount of yarn you’ll need to buy in your substitute yarn. Divide the total amount of yarn needed by the yardage in your substitute ball and that's how many balls you'll need. Always round up here: way better to have an extra ball (hello, matching hat!) than to come up short.

Swatch, and swatch again

Swatch your substitute yarn and see how it compares to the pattern. Does the gauge match up? Can you tell how it will hang if it’s a garment Keep swatching until you know you've got it right. You will definitely thank yourself later.

Ask around

Knitters LOVE to share advice, especially when it involves yarn choices. When I’m in doubt about a specific yarn, I try to find other knitters who may have substituted that same yarn to see how it turned out for them. Often knitters will blog about projects and have useful advice regarding the yarn they used. Take a look at how their project compares to the one you’re working on in terms of drape and gauge.

You can also look up specific projects online to see what other yarns knitters have used for that pattern. You’ll know right away whether you like the drape and overall look of the yarn.

Another online resource I find helpful is Yarndex . You can look up nearly any yarn there — even discontinued yarns — and find out information like weight, gauge, fiber, and everything else you need to know to compare a substitution. You can also search using criteria like weight and fiber content to browse substitution options. If you know you need a merino blend in sport weight , for example, you can put both those terms into the search and see all the yarns that meet those criteria.

October 04, 2018
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How to Substitute Yarn