needle size is immaterial

Yes, this is a post in which I reiterate a frequently made point: that while gauge is really important when you are knitting a pattern, needle size is completely immaterial.

When you want a hand-knitted item to fit correctly, the only thing that matters is that the fabric you are knitting is as similar as possible to the fabric the designer wants you to knit. That is, that you are knitting with the same number of stitches and / or rows per inch (or per 4 inches, or 10cm) listed in the pattern. It doesn’t matter if the designer achieved that fabric on a 2.5mm needle and you need to use a 6.5mm needle. It is only important that the gauge matches. The needle size is immaterial.

Mel and I have been knitting together for many years, and we know that our gauge with the same yarn on the same needle can vary wildly. If I swatch for a pattern, on a certain needle, Mel generally finds she has to go up at least two needle sizes above mine to achieve the same gauge and the same fabric. Swatching and matching gauge is the most crucial element of our pattern writing and sample knitting process. Our awareness of our different knitting styles, and distinctive gauge-y anomalies, frequently informs the way we work. For example, because I find I often achieve a weirdly ‘square’ gauge when knitting colourwork (that is, a gauge with the same number of rows as stitches to the inch) and because this is quite unusual (few other knitters, it seems, produce this) we’ve found it can be useful for Mel to knit a swatch to the same stitch gauge, and for us to take the row gauge in the pattern from her swatch rather than mine (because, overall, the gauge of her swatch is most like the ‘average’). So while we are continually thinking about gauge – and how best to swatch – Mel and I do not think about which needle size we knit with because we know that needle size is immaterial. In creating samples and writing patterns, we are only ever aiming to achieve – and to measure accurately – a certain number of stitches and rows per inch.


One of the most frustrating things as a designer is when a knitter pays no attention to a pattern’s gauge or swatching instructions, but simply looks at a pattern’s recommended needle size, and casts on. Then they get in touch to let you know the thing they knitted doesn’t fit.

“it’s so big I’ll have to felt it”
“it’s so small it wouldn’t fit a child.”
“did you swatch?”
“no.”

It might surprise you that such exchanges most often concern accessories : gloves, shawls, hats. This is, I suspect, because while knitters are generally happy to take the time to swatch carefully before knitting any garment they actually want to fit properly, they are bizarrely unwilling to do so for a hat. The lure of the small, quick knit is irresistible. There is yarn at the ready. The pattern includes a recommended needle size. Knitters don’t check their gauge, but simply cast on right away.

In 2015, I was developing my first yarn (Buachaille), and one thing I knew from the outset was that I didn’t want to list a recommended range of needle sizes on the ball band. First, I was aware that seeing a needle size prompted knitters to think of a yarn in ways that might be misleading (“that’s obviously a 4 ply”, for example – when the yarn might not be that at all). Second (and perhaps more importantly) I knew that seeing a black-and-white statement that this yarn should be knitted on a certain needle size made many knitters feel uneasy about the necessity of working with a needle that could be many sizes larger or smaller than recommended to achieve a pattern’s listed gauge. I really wanted knitters to feel more confident and more relaxed about gauge – and achieving such confidence to a certain extent means forgetting about needle size – because needle size is immaterial. So I hatched a plan to dispense with recommended needle sizes altogether in my pattern writing.

At that time, I was developing a collection of accessories and I thought that rather than starting the pattern with my usual:
“Cast on with 3.25mm / US3 needle” I would instead say:
“Cast on with gauge-size needle,” re-emphasising the fact that gauge, rather than the dimensions of the needle, was the only thing of importance.

This was a decision with which, it has to be said, my technical editor was not at all happy. We began to release the patterns as part of our weekly club, and it turned out knitters weren’t happy with it either:
“Can’t you just give us an idea which needle size was used?”
For a short time I brazened it out:
“just swatch, and find which needle gives you gauge” – but the clamour grew ever louder. Knitters really wanted to see a recommended needle size, and so I was encouraged – and felt compelled – to provide it. My compromise was that my patterns would list the size of needle with which each sample was knitted with a clear disclaimer that this was provided for information only, and was in no sense a substitute for careful swatching.

Describing needles as “gauge-size” and including a needle size “for information only” has been our practice going forward. We receive a small number of queries about our somewhat unusual nomenclature: “what on earth does gauge-size mean?” But it only takes a moment to explain that “whatever needle gives you the gauge specified in the pattern is your gauge-size needle,” and frankly I would rather we dealt with such queries than those of the “it doesn’t fit” variety. In the three years since our introduction of the “gauge-size” wording, I would say we’ve had far less “it doesn’t fit, and no I didn’t swatch” enquiries than previously. It’s difficult to say if that’s because we’ve shifted the emphasis from needle size to gauge, and continually reiterated the importance of swatching, but whatever the reason, it is good to see.

And yet, I was prompted to think again about my compromise of including a “recommended needle size” in our patterns when putting together our Milarrochy Heids collection. All of the hats in this collection were knitted in the same yarn – Milarrochy Tweed – but the samples and patterns were created by thirteen different designers. I knew that gauge can vary very widely, but I was still surprised to discover how differently our designers knitted. Some were clearly super-tight and others obviously super-loose knitters. In one example, using the same needle size, across a 4 inch swatch, there was a seven-stitch difference in the gauge achieved by two different designers. This created something of an editorial conundrum for us. The patterns were all knitted in the same yarn. Did we effectively introduce a technical inconsistency into the collection (and also potentially confuse knitters) by suggesting, in one pattern, that they knit with a 3mm needle to achieve a gauge of 23 stitches per 4 inches, and then, in the next pattern, suggest that they knit with a 3mm needle to achieve a gauge of 30 stitches per 4 inches, using exactly the same yarn? Or did we (my preferred option) dispense with recommending needle sizes altogether, simply list the required gauge, and instruct knitters to swatch to achieve the right fabric on their “gauge-size” needle?

Once again, I was counselled against dispensing with listing a recommended needle size (not least by some of the designers). So I looked at other edited collections of patterns produced by different designers that used exactly the same yarn. There were different approaches to this issue, but reading between the editorial lines, it was obvious that the most common solution was to list what was effectively an ‘average’ recommended needle size for any given gauge. This meant that if the numbers of stitches per 4 inches differed significantly, so did the recommended needle size. So we decided to try this approach for Milarrochy Heids. Looking across the patterns, and the range of needle sizes used, it was fairly easy for my editorial team and me to develop a sense of what an ‘average’ gauge might be on a 3mm, a 3.25mm, a 3.5mm needle and so on. If we associated each gauge with the average needle size used to achieve it, we’d avoid introducing a potentially confusing technical inconsistency, on the one hand, and, on the other, avoid the wrath of knitters upon opening a book completely devoid of recommended needle sizes (the horror!)

So listing what was effectively “average” needle size for information only was our compromise with each pattern for Milarrochy Heids. Yet, throughout the editorial process I’ve remained unhappy with this compromise. I knew that the designers might feel freaked out (or irritated) that their pattern’s ‘recommended needle size’ was not, in fact, the one with which they knitted. I also knew that there was the inevitable likelihood of some knitters simply glancing at the recommended needle size rather than the gauge and casting on – ignoring my strongly worded, and continually reiterated, instructions to swatch.

So in the book I included the following clear statement:

“Though all knitted in Milarrochy Tweed, these hats are as different as their designers, and are worked at different gauges. Gauge is crucial to the fabric the designer wishes to achieve as well as the fit of the finished hat. So it’s important to swatch and, if your gauge does not match that which is specified in the pattern, to swatch again, going up or down a needle size where relevant. Whichever needle gives you the specified gauge is your “gauge-size needle.” You’ll usually select the size immediately below for your “below gauge-size” needle, unless differently instructed. Don’t rely on your instincts (“I always knit with this yarn on an xx needle”) and please don’t simply start knitting with the needle upon which gauge was achieved in the sample (which is included in the pattern for reference only, and a starting point for swatching).”

Anyway. All of this is the context of just one of the many behind-the-scenes decisions and compromises that I have to make in consultation with my editorial team when developing a collection. I describe it here because – only a week after publishing Milarrochy Heids – we have become aware that knitters are not swatching or checking gauge before casting on their hats and are simply casting on with the ‘recommended’ needle size . . . with the inevitable result of a finished hat which does not fit as well as it should.

So may I once again reiterate the key – and really the only point – that ever needs to be made regarding gauge: the needle size with which you knit is completely immaterial. The only thing that matters is that you achieve the gauge listed in the pattern, and the only way to do that is to SWATCH.

Here endeth the lesson.

Perhaps one day I will feel brave enough to stop listing needle sizes altogether. Who knows?