How To Convert Yarn Weights to Yardage

83957540_cbecbd2247I know you’ve had the experience.  We all have.  You have a pattern that calls for a certain yarn and lists the amount in grams.  But what if you want to make a yarn substitution?  How much of the new yarn do you need?  Or you have a bunch of yarn you’ve lost the ball band for and have no idea what the yardage is?  Yup.  I’m pretty sure you’ve been there, too.  So how do you know how much you have, or what you can do with it?

The trouble with yarn weights is that you have to know the size of the yarn (lace, sport, DK, worsted, etc) in order to understand how many yards you have.  The spinning process involves stretching the fibers out to a specific thickness which correlates to a specific length, as well.   That thickness…or thinness…will determine how long you have to tease out the fibers.  If you take 100 gm raw fiber and spin in into a super-super chunky blob of yarn that gets 1/2 stitch to the inch, you won’t get anywhere near the same yardage as you will get if you pull it thin, thin, thin to a super-fine lace weight.  Same 100 gm, very different yardage.  So how will you figure out the yardage based on the weight?

The first thing you want to know is the gauge of the yarn your pattern calls for.  Stitches per inch or stitches per four inches should be written in your pattern along with a recommended needle size, and should also be on the new ball band.  Recommended needle sizes are pretty standard for most things.  Yes, I know that there are some designers who like to play with out-side-the-box gauges.  Still, the majority of the time, there are some standards.  Knowing the recommended needle size and gauge will help to identify the size of your yarn.  The ball band will also tell you the weight of your yarn.  If it matches your pattern, voila!  You’re done.  If it doesn’t, read on.

If you have no ball band, you’ll have to get a little bit craftier.  A while back, in our newsletter, we gave you a WPI (wraps per inch) chart that gives you a pretty good idea of the gauge of you yarn.


In case you didn’t print it out and save it, here it is again.  (Or you can read the whole article on how to check your WIP in the newsletter, here.  Scroll all the way to the bottom and read the Yarn School segment.)

After you check your wraps per inch and have a pretty good idea about what size yarn you’re talking about, you will want to weigh it.  If the weight matches your pattern, you have a pretty good idea that you can make the substitution.  If not…well…





















Since you’ve figured out the thickness, or thinness if you prefer, of your yarn based on either the ball band or the WPI chart, you just need to know what the standards are for yardage of that weight for that size, right?  Here you go.



You can print these charts and keep them in your knitting library and never be in doubt again.




Written by mim


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