WPI stands for Wraps Per Inch. And you may wonder what is it and why you need to know about it.
Very simple, this is a system that allows you to know the ga approximate yarn weight by checking how many wraps of yarn fit in one inch or 2.5 cm, I prefer to do it in inches because I find it more accurate.
What is the purpose of knowing the WPI of a yarn?
Surely you’ve had a yarn that you don’t know its weight, and you want to know if you can use it for a certain project.
You bought a pattern, and it asks for a yarn that you don’t have, but it tells you the WPI of the yarn you should use. If you know the WPI of the yarn you have, you will know if you can use it or not.
How do you know how many WPIs a yarn has?
There is only one way, but you can use several tools to do it.
You should take a ruler (or anything that has 1 inch measurement) and wrap it loosely around the yarn within the measurement corresponding to one inch or 2.5 cm.
If you don’t have a ruler or want to use a tool just for that, you can take any object, for example a pencil, and mark with tape or anything else the space that measures one inch. Clearly you will need a ruler or tape measure to measure, but only the first time. Then you know that there is one inch in that space.
There is a tool that already comes for this, it is basically a small ruler with the measurement of 1 inch. They are very nice but not essential to know the WPI.
I use the ruler to measure the samples and the hook measurements to do it.
How to Know your Yarn Weight depending on how many WPI it has.
This is a very simple method, I promise it will get you out of a lot of trouble. Tell me what you think, have you used it before?