First, let me say that the suggested knitting needle sizes in a pattern are ALWAYS, ALWAYS, ALWAYS a suggestion. The size of needles that a knitter might need changes drastically for a lot of different reasons. The type of yarn, the type of needle, your mood, the weather, and the stitches you are knitting can all make a difference.
As a designer, I never want you to use the exact size of needle I’ve suggested in my pattern if that won’t work for you. Instead, when I list a suggested needle size on a pattern, I am making an educated guess about what needle size is likely to work for a majority of knitters for the project.
And it really is a guess. Because even if you use exactly the same yarn and exactly the same type of knitting needles, the way you knit will still be different from the way others knit. I always hope that a knitter will think about my suggestion through the lens of their own personal experiences and then go completely rogue to choose the needle size that makes the most sense to them!
I always add a note like this in the Pattern Notes of my patterns.
Test your gauge! These are recommended needle sizes but you will need to use the size of needle that gives you gauge in pattern. If the fabric feels too loose or the stitches lack definition, you likely need to go down a needle size. If the fabric feels too dense or the stitches are hard to work, you likely need to go up a needle size.
– note found in every knitting pattern I write
And that’s a big part of why a test swatch is such an important step in the knitting process. I wrote a whole blog post here about why you should do test swatches. And testing different sizes of knitting needles is definitely something you’ll want to do with your test swatches. Once you’ve gathered your data from your test swatches using different needle sizes, you can measure the number of stitches and rows (or rounds) per inch and make your decisions from there. You’ll want to consider which needles help you achieve the written gauge of the pattern, which needles make a fabric that feels good to your hands as you work, and which needles handle the pattern and stitches best for you. If your data tells you to use a different size needle than is suggested on the pattern, you should absolutely do that!
That’s why I always say — Go rogue and use the needle size that will work for you!!!
