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The most accurate way to tell how much yarn you’re using up or will need for a project is to measure the length. Unfortunately, this often isn’t practical. In order to accurately determine the length of yarn used, many designers use a work around by weighing the yarn. Even if you aren’t a designer, you’ll probably find weighing your yarn to be useful.

Why you might want to weigh your yarn:

  1. Because you want to know how much yarn you’ve used up and how much you have left. If you use 80 grams of yarn for the first sleeve, and you know you only have 70 grams left, then you know you don’t have enough. Yes, it’s depressing, but it’s better to find out now, BEFORE you knit almost all of that second sleeve and run out with only 10 rows to go.
  2. Because you want to know how long you can work even. A lot of patterns have a shaped beginning, a work even middle, and then a shaped ending that matches the beginning. By figuring out how much yarn you used for the beginning, you can estimate how much you need for the ending (I add 10% for safety), and then you know how much yarn you can use for the middle. This lets you get the biggest shawl or longest scarf possible.
  3. Because you want to know how much yarn to buy. If making one 9 inch motif square takes 25 grams of yarn, then making a baby blanket with 25 squares requires about 625 grams of yarn.


  • Always weigh your yarn before you start. The weight of yarn listed on a label is almost always the weight BEFORE being dyed. Once the yarn soaks up dye, it’s heavier. You’ll often find that a skein of darker yarn weighs more than a lighter yarn because the darker colors require more dye.
  • Always weigh the yarn you’re actually going to use. Let’s say you make a motif in 25 grams of yarn A. That weight is only accurate for that yarn in the colorway. If you want to make the motif in another yarn or another color, you need to change that gram measurement to yards first. How? Grab a calculator.

Step 1: Multiply the weight of one motif times the yards of yarn in the whole skein (you get that info off the label).

Step 2: Divide your answer from Step 1 by the weight of the whole skein from before you started.

That’ll give you the yardage.

  • I recommend using an inexpensive postal scale to weigh yarn. I purchased mine for $15 at target, but you can buy a similar one like this online. The best kind can give measurements in both grams and ounces.

In Part 2 of Weighing Yarn, I’ll discuss why I prefer to weigh in grams rather than ounces. If you have any questions about weighing yarn, comment with them here so I can answer them in my next post.