So, You Want To Substitute A Yarn In A Pattern?

July 2, 2025

We’ve all been there – browsing knitting or crochet patterns, something catches your eye and you are immediately smitten! You’re ready to get started!

But you don’t want to use the specific yarn the pattern recommends (or it's not available) – you want to use your favourite BWM yarn!

How do you know what to do?

Sometimes it’s simple! All of our 8 ply wool yarns have similar properties, which makes it easy to make a swap... a pattern for Luxury 8 ply will work just as well in Whisper 8 ply, Rustic Tweed 8 ply or most of our limited-release 8 ply wool yarns too!

But other times, the substitution is a little more complex.

Perhaps the pattern calls for two strands of a lightweight yarn like Lilt (like our new Sofia Jumper), or was made for an unusual, no-longer-available yarn.

So, what’s a crafter to do? It’s yarn substitution time!

There are three key aspects to ensure your yarn substitution is successful.

Matching gauge/tension
Matching fabric properties
Calculating quantities

We’ll explore each of these aspects in detail below so you’ve got all the info you need to make your unique project a success!

Note: this post will explore how to substitute a yarn to a pattern without adjusting the pattern itself. If you’re wanting to substitute a different weight yarn into a pattern (eg changing a 4 ply pattern to knit in 8 ply), you’ll need to do some maths and adjustments that are out of the scope of this article.

1. Matching Gauge/tension

We all know how important it is that your knitting/crochet has the appropriate tension. (If not, read our primer on tension here). Otherwise, your project will be bigger or smaller than it should be...and no one wants to wear an ill-fitting garment or try to keep their knees warm with a rug the size of a tea towel! So, your substitute yarn needs to be able to match the gauge (number of stitches in a given measurement) required by the pattern.

The easiest way to check this is by making a swatch of your planned substitute. But if you don’t have it on-hand, you can check the product page or your shade card for an idea of what’s achievable. For example, according to the label & product page, our Classic 8 ply knits up at an average of 22 stitches and 30 rows per 10cm on 4.00mm needles.

Other combinations that might give you a similar gauge are holding two strands of Lilt together, or one strand of Lilt and one of Multicoloured Sock Yarn 4 ply.

Checking other patterns will help too! For example, our Isabella Top-Down Yoke Jumper uses a strand of Lilt and a strand of Luxury 4 ply or Multicoloured Sock Yarn 4 ply together for a gauge of 22 stitches and 30 rows on 4.00mm needles – so this combination might work for an 8 ply pattern like this Toni Vest. Making sure your substitution can be knit/crocheted to a similar gauge to the pattern is the first step to substitution success!

2. Fabric Properties

Every Bendigo Woollen Mills pattern has been carefully designed and tested to create a finished product with certain properties – drape, stretch, warmth and structure.

Our Caroline Tee was designed for Cotton 8 ply at a gauge of 22 stitches to 10cm using 3.75mm needles, taking advantage of Cotton’s properties to create a relaxed top that drapes softly for a flattering, comfortable fit.

If you knit it up with Luxury 8 ply instead, you would get a firmer, warmer fabric with a less drapey fit. If that isn’t what you’re looking for, then finding a yarn with similar properties would be better.

We knitted this pattern up using Dolce 8 ply (a limited-edition blend of wool and bamboo with fantastic drape) and we loved how it worked up!

3. Calculating Yarn Requirements

If you’re happy that your selected substitution can give you a comparable gauge and the desired fabric properties, it’s time to calculate how much yarn you need!

Weight isn’t a good way to calculate yarn substitutions: different fibres have different densities. So we need to calculate based on LENGTH. Our patterns all specify quantities in the recommended yarns.

The Eliza Jumper requires 5 balls of Elixir 16 ply for the 100cm size. To substitute a different yarn/combination of yarns, you’ll need to calculate your quantities based on the required length.

The formula is: Quantity of balls x number of metres per ball = total length requirement.

Elixir has 180m per 200g ball – so the total meterage required is 5 balls x 180m per ball = 900m of yarn.

If you wanted to make it with a combination of Luxury 10 ply and Luxury 4 ply (like Jessica has done here) held together like one yarn, you’d need 900m of Luxury 10 ply and 900m of 4 ply. This equates to 3 balls of 10 ply and 1.25 balls of 4 ply.

Note: Be careful not to confuse metres and yards! Patterns and yarns from outside of Australia often use yards, you’ll need to convert to metres to do your calculations. And remember, if you’re holding two yarns together, you’ll require the full length in EACH yarn to make the same total length when they’re held together.

Other considerations

Stitch definition: if you substitute two strands of Lilt into a Luxury 10 ply cable pattern like this one, your cables will be less defined because of the gentle halo of mohair.
Colourwork: when doing colourwork, you typically would want to use a yarn with some elasticity, which will sit better and more evenly in detailed colourwork designs. Depending on the pattern, an untreated, hand-washable yarn like Rustic Tweed will also make your fabric more consistent and neat in a colourwork design.
Warmth: substituting a warm, woolly yarn for a lightweight Summer Cotton will create a very different garment!
Care requirements: a jumper for a rough-and-tumble toddler that’s designed for Classic 8 ply will be a bit more work to keep clean if you choose a delicate combination of hand-wash yarns!
For older and more unique yarns, checking a website like Yarnsubcan be helpful to find the specifics of what you’ll need in your substitution.

We hope this guide helps you expand your creative limits & explore new combinations, textures, and colour effects!