The Great Swatch Experiment

You probably know that we’re big fans of swatching here at Berroco, but maybe you don’t understand why. What’s the big deal? “Swatches always lie,” right? Who has time to swatch, just get to the fun part! But believe it or not, swatching is an integral part to knitting and crochet projects that have to fit a body part. You can 100% skip a swatch for a scarf or a shawl (although I would argue that swatches can still impart valuable, time-saving information even for accessories), but if you want a garment to fit, swatching is crucial. Not convinced? Maybe this post will help.

This summer, I asked for volunteers from our Ravelry group to help me out with an experiment. The deal was, I would send them a ball of Berroco Ultra Wool, and they would in turn send me back a swatch knit with size 8 (5mm) needles, to my specifications. Everyone knitted a swatch that was 24 stitches across, with 5 rows of garter, followed by 25 rows of stockinette with 3 garter stitches on each side, followed by 5 more rows of garter. The result was 24 swatches made with identical yarn on the same needle size by 23 different knitters.* As I expected, the results were illuminating!

I ran a similar experiment with crocheted swatches. But for the purposes of this post, I’m going to focus on the knitted ones, because I have a larger sample size and the results were fairly similar in both cases.

IMG_5474As I expected, there was quite a wide range of sizes across all the swatches that I received. The largest swatch was over an inch larger in each direction over the smallest one.

For the purposes of the data, I measured only the stockinette portion of the swatches, not the garter stitch border. Also, while the garter stitch border does distort the stockinette stitch portion a little bit, I’m not very worried about that in this case, as I would expect that to be more or less consistent across all swatches. I measured across the middle of the swatches.

After carefully measuring each swatch to the nearest 1/8 inch, I put all the data into a spreadsheet and crunched some numbers.

Berroco swatch experiment-final results-knit

I have highlighted the ball band gauge in the results, which I’ve sorted by stitch gauge. The knitters at the top of the list have the loosest gauge, while those at the bottom are the tightest. This provides a good reminder that your width and your stitches per inch are inversely proportional; that is, the smaller your swatch, the more stitches you can fit into each inch, and if you were trying to reach a specific gauge, and have too many stitches per inch, you would likely want to go up a needle size or two.

Predictably, the ball band gauge is right in the middle. You may wonder how we determine the recommended gauge for Berroco’s yarn labels. As the yarns are swatched by the design team, we try out different tensions to find a nice even tension for the yarns. Sometimes there is a range of gauges that we choose to list on the label, when a yarn looks and feels nice at multiple gauges. The final determination of the official gauge is made by our design director Amy Christoffers. However, the needle size we list on the label, and the “official gauge swatch” that we keep in our files, is from our technical writer Brenda York, whose tension tends to be right in the middle, not very loose or very tight.

In the last two columns, I’ve listed the percentage difference for each swatch over or under the ball band gauge. If we look at the stitch gauge column, we have six knitters who got the ball band gauge with the recommended needle. But the majority—18 out of 24—did not. I am in the group who did not; my swatch was 7% tighter than the ball band gauge. That may not seem like a lot—I was only off by about a quarter of a stitch per inch! But, if I were making a size 45″ sweater for myself, it would wind up being about 3″ smaller than the intended size.

Another interesting statistic to look at is the variation in row gauges. As you see in the table above which is sorted by stitch gauge, the row gauges column does not follow exactly the same pattern as the stitch gauge column. That means that different knitters had a different ratio of stitches to rows, and I added a column for that ratio. This is another area where knitters often fudge their gauge results; we’ll make sure we’re getting the correct stitch gauge, but if the row gauge is off we might not worry too much about it. And that is okay for the most part—most patterns are written with the lengths listed for sections rather than the rows. But you can run into trouble if your ratio is very different from the pattern’s when it comes to things like raglans and sleeve caps, and even picking up stitches for a button band or collar.

Surprisingly, while we had six knitters match the stitch gauge, not a single one matched the row gauge in our sample! In an ideal world, our official Berroco swatcher Brenda would be exactly in the middle of all knitters, a perfect average, but this just goes to show that we really all do knit differently.

In conclusion, ladies and jellyspoons, SWATCH! At least when you are making something that you want to fit. And then keep measuring your gauge throughout the knitting process, because I bet if I asked these same 24 knitters to make me another identical swatch on a different day we’d get 24 new sets of numbers. Swatch, but always remember that swatches lie.

* Our friend Gabi, ever the over-achiever, sent in two knitted swatches made using different brands of needles. I want to do a whole other experiment where knitters make 2 or 3 swatches using the same yarn, same needle size, but different needle brands/materials, to see how that can affect gauge. But that is for another time.

32 thoughts on “The Great Swatch Experiment

  1. In your test, did the knitters process their swatch? i.e. soaking, washing, steam etc
    Those processes also change gauge, both stitch and/or rows.

    1. That is an excellent point! The instructions didn’t say to wash/block/steam/etc. and those that asked, I told not to do anything to it. However, it’s entirely possible that a couple did anyway. I am the first to admit this experience probably doesn’t hold up to seriously scientific scrutiny but I tried to keep it as consistent as possible.

  2. Thank you for conducting this experiment! The photo with the largest and smallest swatch should become a mandatory addition to each pattern, because it explains the “why swatching” excellently. And very interesting stitch/row observation!

    Well done, and thank you for sharing your findings with us!

  3. Another thing to check for would be technique – while all knitted, some may throw, some may pick, some may be Continental, some may be combination, etc. Any of these may have an effect on gauge. There may also be regional differences based on the most predominant techniques or teaching – for example, I was taught combination, but the person who taught me taught everyone in the area for over 50 years before I came along, so everyone in the area knit the same way and we had very little problems with things like ‘everyone make a square’ charity blankets as the squares turned out fairly similarly as a result.

    1. Now people would just teach themselves from the internet, but back then it was passed on from person to person and it just worked out that way for us as she was part of the hospital auxiliary and church charity group and was willing to do it. It may not be as common now!

  4. When I swatch I attach a shipping tag with not only the needle size but the brand, the material (wood, stainless, aluminum, plastic, bone?) and whether straight, dp or circular.
    It really helps with those projects I put aside for a while or steal the needles from.

    1. WOW. That is so smart. I vowed recently to start tagging crochet hook size but you are right — the other criteria are important also.

  5. I was anxious to see what the results would be with your experiment. I am very surprised at the differences in swatch sizes.
    Thank you for showing it on your spread sheet.

  6. Very interesting blog post! The picture was very helpful as well. After you finished all of the measuring and spreadsheeting, did someone sew all of the squares together? This would make a nice donation to a pet shelter.

  7. It is all so confusimg, and why I have yet to make myself a sweater. Should one wash and block their swatch before measuring? And how do you figure out which size to actually knit based on your swatch measurements? Were things this difficult in my great-grandmother’s era?

    1. I know, it’s a lot to think about! To take your questions – yes, you should definitely wash and block your swatch before measuring, because that can definitely affect the gauge. Then figuring out which size to make – if you get the designer’s gauge, you can simply choose the size to knit based on how you like your sweaters to fit. (I think the best way is to find a sweater that fits you the way you like, and make the size closest to the same finished measurements.) If you can’t get the designer’s gauge even with a different needle size, it can sometimes be a good plan to use one of the other sizes’ stitch counts, but that does involve some math. (Stitches per inch x desired number of inches across, etc.)

      And I’d say, the biggest change in knitting from earlier generations is that knitters had their mom, grandmother, aunt, sitting next to them while they knitted, passing down all that information in real time! Nowadays, most of us don’t have that, so instead we are just googling for answers all the time. It can be nicer to have a person who can see your knitting and react to what you’re doing. This is one of the reasons I love yarn shops that have drop-in knitting classes, or knitting groups, where you can actually talk with expert knitters in person.

  8. I recently became a semi-reluctant swatching convert (for garments, anyway), as part of my experience knitting the Berroco Abayomi pattern. I REALLY wanted to just jump straight into the project instead of swatching, but in the end I was SO glad I swatched first! Swatching made a huge difference, though…I learned that I had to drop two needle sizes — and wet block — to get the correct size. Had I just used the needles called for in the pattern, my sweater would have ended up 7.5” bigger in the final bust measurement. I did my own blog post about the experience, because it impacted me so much as a knitter:

  9. This is a timely article for me because I just finished a test knit for a Ravelry designer a few days ago using Berocco UltraWool and I did not swatch (gasp!). Generally I don’t swatch for hats as I would for a garment, because it’s a hat–it will fit somebody, right? In fact, I often buy an extra skein and make a hat with it to serve as my swatch for a bigger project that will be knit in the round. I had a bit of a scare with the test knit because the hat grew A LOT in length when I washed it. I hadn’t used UltraWool before, so I thought I had some reknitting to do. But the good news is, once the swatch was truly, completely dry, it had bounced back to the original proportions.
    Takeaways: 1) Wash those swatches the same way you plan to wash your FO and then **be patient!** It takes a pretty long time for knits to dry completely, especially if you live in a humid climate like I do. And 2) Yay for the bounce-back power of UltraWool. I’ll definitely knit with it again.

    1. Thanks for sharing this experience! We have definitely found that Ultra Wool grows when it’s washed. If it doesn’t bounce back drying flat, you can put it in the dryer. Yes, the dryer! (On low.) I would normally never do this with anything hand knit, but Ultra Wool holds up very well and bounces right back to shape when machine dried. Go figure! (Just don’t try this with anything with fringe – we tried that once and the fringe turned into fluffy fiber.)

  10. I have personally conducted your next experiment – comparing gauge with different needle surfaces. I, myself, find that I can knit tighter with metal needles than with wooden. For what it is worth, my flat knitting gauge is also much different than circularly.

    1. It’s very common for folks to have a different gauge knitting flat vs. circularly. In most of these cases it seems like people purl a little more loosely than they knit; sometimes you can even see the difference in gauge purling vs. knitting on flat stockinette stitch. Thanks for sharing!

  11. I would add two things to the label I attach to the swatch: 1: gauge obtained before & after blocking and, 2: whether I knitted it English or Continental style. If the gauge changes with blocking, it’s important to know that when measuring the item while knitting. It’s also important to be consistent myself with knitting style as, that can affect gauge.

  12. Fascinating. I am going to copy and print the whole article and keep in my “techniques” folder, where it will hopefully remind me to swatch all the time. Curious…did some of the knitters use Continental and others English method? Should be the same, but then again, your article proved that those assumptions can be wrong.

    1. Great question! Unfortunately I didn’t think to ask the swatchers whether they were knitting continental or English, but I think it’s a fair assumption that probably there was a variety. I’m tempted to reach out to them again to ask, to see if there is any correspondence between either style and a looser or tighter tension.

  13. One other consequence of a swatch gauge that is greater than the ball band row gauge may give you a hint that you should run back to the shop and buy that extra ball. You may be knitting 30 or 40 more rows to get your length than the pattern garment knitter took.

    1. Excellent point! We do build in some cushion in the yarn amounts to account for variances in knitting, but it’s definitely a good idea to pick up an extra ball of yarn just in case.

  14. I was a lab rat for this and it was fun! In my real world knitting, I may or may not swatch depending on the project. I’m so glad to see these results and I’m surprised I was close to guage but was actually on the tight side. I generally just automatically go down one needle size than what the pattern calls for because I tend to be loose. Just goes to show that, while we all probably knit the same general way every time, it is best to swatch because of these variations. For the record, I knit English (throw rather than pick)

  15. I wish that the pattern makers would list the needle brand they use. I find Berroco particularly challenging. Case in point: Anhinga. This pattern has been reissued and I went with that one. I found it overgauged (size 9 needles) but I guessed it was on purpose for the fabric would drape gracefully since the sweater has such a strange (but seductive) shape. I have bags of Berroco Merino because of stubborn ungauged swatches.

    1. From this limited sample set, I didn’t see any correlation between what brands of needle people used and their gauge. So, I don’t think that patterns listing the needle brand would be very helpful to knitters trying to achieve the gauge. From everything I’ve seen, it seems like it’s all down to how different knitters hold their yarn and the amount of tension they use while knitting. I’ve been starting to gather some info from the folks who made these swatches about whether they knit Continental or English, and I am not even seeing any patterns from that so far.

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