A Guide to Yarn Substitution

by Montague - 10th November 2021
"What yarn should I use?" The million dollar question I'm sure you ask yourself almost every time you start a new crochet project.

You have a pattern you're excited about but when you look at the suggested yarn you realise that it's either unavailable in your neck of the woods, has been discontinued or is too expensive – or you'd rather use some yarn from your own (ever-growing) stash.

You can't help but feel a little bit disappointed, or even a bit frustrated sometimes. Until you realise that although substituting yarn can be a complex thing (entire books have been written about it!), it really doesn't have to be.

Sure, we can talk about fibre content, structure, texture, drape and all that jazz, but that's really unnecessary 99% of the time. In the rare situations where that does come into play (and it's mostly limited to specific types of garments), experimenting with a few different yarns on a gauge swatch will generally do the trick. If not, you're probably doing some really specific stuff and this post is not really intended for that. You should go have a look at one of those books I mentioned!

For the absolute majority of projects though, there's a very quick and super simple method that will make substituting yarn a breeze, and you can be confident that your finished item will look just like you expect it to.

So come on Monty, out with it! How do you choose a different yarn for a crochet pattern?

The best way to choose an appropriate yarn for a project is to calculate its length per gram/ounce and compare it to that of the yarn listed in the pattern.

The goal is to use a yarn which is as close to this as possible, ideally with a difference of less than a 0.25 metres/yards per gram.

It's that simple.

How do I calculate the length per gram (or ounce)?

Each ball/skein of yarn will tell you how long it is and how much it weighs in grams (or ounces). If you divide the length by the weight, you'll get the length per gram.

For example, in our Ribbed Placemat crochet pattern we use Catona, by Sheepjes. Each ball/skein weighs 50g and is 125m long. 125/50 = 2.5m per gram. So anything between 2.25m and 2.75m per gram should work well.

It doesn't matter whether you're using yards or metres, ounces or grams. Just make sure you're using the same for both of the yarns you're comparing; metres to metres or yards to yards. Don't mix them up!

Where can I find the length and/or weight of a ball of yarn?

If the yarn you're considering is already a part of your stash, this information should be on the yarn label itself. Similarly if you're browsing yarn at a physical shop. When shopping online, this information will be available on the product page itself.

In the case of the pattern's suggested yarn, a well-designed pattern will provide this information directly. If not, you can look it up directly from the manufacturer's website, or from any online store which carries it.

Experienced pattern designers will provide details on the yarn they use for clarity and convenience. This is one example of how it's done; it's a screenshot of the yarn section of our Honeycomb Luminaire pattern. The weight category, weight (actual) and length of each skein are all listed. We also provide the length-per-gram calculation ease of reference, and as a reminder of what to look for when substituting yarn.

Is there something I should avoid?

Yes. Don't use a yarn's weight category (eg. Fingering, DK, Aran) to determine whether it's a good substitute for the one listed in the pattern. If you do, you might be disappointed to find that the size of your finished piece is not what you were expecting.

This is due to the variations within yarn weight categories. Each weight represents a range of yarn thicknesses. These ranges are broad, not precise and, more importantly, not universal. Each yarn brand/maker might have their own way of categorising their yarns. To make matters worse, different fibres have different densities. So, gram for gram, two yarns of equal thicknesses might have completely different lengths.

While I see some value in grouping (arbitrarily) similar yarns into a handful of categories, the current system is far more misleading than it is practical (for reasons that I will not go into right now as they are beyond the scope of this post and because I'm dangerously close to turning this into a rant, which has been known to happen ?). However, the weight categories are good as a general starting point to help you narrow down your options.

Still unsure?

Don't fret! Just send us a message and we'll happily help you out.

You could also ask for advice from the helpful community of crocheters over in our Ava & Montague Club. It's free to join and you'll get access to our library of home décor patterns, a growing community of fellow crocheters, plus a whole bunch of other perks and features. You should check it out!

A side note on gauge

As with all handmade items, some size variation is to be expected. With home décor items, this is not much of an issue as long as the difference is small. By using the method of comparing a yarn's length per gram you'll ensure that these variations remain insignificant.

If you happen to be working a gauge swatch, it will help you find the right tension for your project and apply minor fixes such as changing your hook size. But only if you're using the right type of yarn as discussed above. Otherwise the variations will be beyond the scope of checking for, and meeting gauge.

This is not meant to be a commentary on whether you should work a gauge swatch or not. I won't go into the merits of why you should consider working one, how to do it correctly, or the different ways you can measure gauge. That's the subject of another post for another day. Personally I believe it depends on the size and scope of the project (and that it's essential if you're working garments), but more on that some other time.

I will however say this: if you're testing a pattern for a designer and that designer asks you to meet a specific gauge, all discussion becomes irrelevant. You have to work the gauge. It's what the designer needs, and it's part of the test.

In conclusion: if you expect to replicate the results of a pattern designer (specifically the finished item's size), don't just pick a random ball of yarn from your stash or the shop. And especially don't trust weight categories blindly. You'll be disappointed with the outcome if you do. Instead, use the simple method described above and you'll be able to pick an appropriate yarn for every project with ease and with confidence.


May we share our newsletter with you?

It keeps you up to date with our latest and greatest, including upcoming projects, giveaways, tips and other fun stuff exclusive to the newsletter.
    There was a problem processing your request. Please try again.

     Blog post categories