Yarn Math

How to calculate yarn yardage using weight

A tutorial from Liz @PurlsAndPixels

Trying to find out how much yarn you need for a project can sometimes feel like a guessing game. Do you have enough? There is one way to be sure. Do a little yarn math.

Find out how much leftover yarn you have with a little yarn math, guide from PurlsAndPixels

These are simple ratios that I remember learning in middle school, but whenever I come back to do them, I have to look it up again. I’m terrible with memorization. If you are too, bookmark this page and come back to it when you need a reminder. That’s what I’ll do!

Measuring Yarn in Yards and Ounces

Most yarn is measured using ounces and yards, rather than feet and grams. We will use yards and ounces for the examples here, but these ratios would work just fine if you wanted to measure in another unit.

Nearly every ball of yarn you purchase new will have a label noting yardage and weight in ounces. After you use some of that yarn, you may want to know how much you have left. Lots of little projects are great for leftover yarn, but it helps to know a close estimate of yardage before you start. To find out, we will use a simple ratio to cross multiply, then divide to find out how much yarn is left.

To find out how much yarn you have left, you will first need to know the weight and length of yarn you started with. This will be written on the label of a new skein. You will also need a scale that weighs in ounces, so that you can get the current weight of your yarn.

Our basic math will use this formula:

Yarn math, a simple formula to help you calculate yardage from yarn weight, tutorial from PurlsAndPixels


Here is an example: If you started with a ball of Caron Simply Soft Yarn, a common yarn found in a lot of places, you would have started with 315 yards and 6 ounces of yarn, as shown on the label.  After you’ve made a project or used some of your yarn, you weighed the leftovers to find that you have exactly 1.2 ounces of yarn left. How many yards is equal to 1.2 ounces of this yarn? Replace y in our formula with 1.2, and complete the math shown in the example to find out your yarn yardage.

Example of how to find out the yards left of yarn just from yarn weight, from PurlsAndPixels

I hope you found this quick yarn math tutorial helpful. Pin it, bookmark it, or share it with your friends using the social links below. Happy crafting!

Yarn Math. How to find out how much yarn is leftover from another project,tutorial from PurlsAndPixels.

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