We all want to be that kind of knitter who can just pick up her needles and create something amazing without really having to think about it, but that's just not how knitting works. Knitting involves math, unless you're experienced enough to be able to just pull approximately the correct numbers off of the top of your head. Things get even more complicated when you factor different yarn weight categories into the mix. How are you supposed to know how many stitches to cast on for an infinity scarf? The long answer is that you need to take the stitches per inch (or gauge) of your chosen yarn and multiply it by the circumference in inches that you want your infinity scarf to be, but the short answer is that there's a general range you'll be looking at, and we've put together a handy chart for you below. The width is completely up to you once you've cast on; you can knit many rows for a stout infinity scarf, or only knit a handful for a skinny scarf. Note that this chart is best if you're using long circular needles and working in the round either top-down or bottom-up; if you plan to knit up a long rectangle (like a regular scarf) and seam it together at the end, your job just got way easier. All you need to do is determine the width that you'd like your scarf to be, and knit up as many inches as you'd like for the circumference of your infinity scarf before seaming it together. For this method, we recommend our chart on How Many Stitches to Cast On for a Scarf. For more great projects like this, subscribe to our free email newsletter!