Thursday, 8 February 2018

Determining Yarn Weights - The WPI Method

I am from a place where you will get yarns of varying sizes but no one actually knows what to call what. In a typical Kashmiri yarn store (that are quiet few and not everyone knows about them) almost no yarn is with a clear label that states what its weight is. The yarns come in great quality and pretty colors but pose a difficulty in understanding its weight and hence in yarn projects.

The weight of yarn is important to understand and know especially when

1. Reading and understanding patterns.
2. When using scrap yarn for scrap yarn projects to use yarns of equal weights.
3. When using a substitute yarn.

Yarn weight Standard.

These standard yarn weight measurements are used and understood universally and used in both UK and US terminology.

0- Lace
1- Super Fine/Fingering
2- Fine/Sport Weight
3- Light/ Double Knitt Weight
4- Medium/ Worsted Weight
5- Bulky
6- Super Bulky
7- Jumbo

How to determine the weight of a Yarn? The WPI (Wraps Per Inch) method.

In case you don't know how to determine the weight of a yarn that has no label on it, like I used to get pretty confused when buying any yarn, then follow this easy and simple method and classify your yarn stash.

It's very easy. All you need is
1. A Binder clip.
2. The mystery yarn.
3. A Ruler.
4. An object with consistent circumference, such as a Popsicle stick or a pencil.

Hold one end of your yarn with the help of binder clip with the object of your choice. Now begin wrapping it around it. Count the number of times you wrapped the yarn around the object for the measurement of 1 Inch. That number will tell you what type of yarn you have.
 Remember not to wrap the yarn too tightly, the goal is to get the accurate measurement of the yarn and not distort it by pulling too hard.

Also, if you are using a yarn with inconsistency, like eyelash yarn then wrap for a bit more than 1 inch to get the accurate result.

You can also directly use your ruler to wrap the yarn for the measurement.

How WPI(Wraps per Inch) works?

The yarn measurement is determined by the diameter of its strand. The circumference of the object doesnt matter because we are working in the diameter of the yarn strand and not on its length and hence that doesnt matter. It makes no difference to the width of yarn strand whether it is wrapped around a popsicle stick, a pencil or a bottle, the measurement will remain the same.

WPI Chart.

0 - Lace weight Yarn

WPI:  > 35 (No of wraps around the object is greater than 35)
Makes up to 9 stitches per inch.

1 - Super Fine/Fingering

WPI:  19 - 22 (No of wraps around the object is between 19 to 22)
Makes up to 7 or 8 stitches per inch.

2 - Fine/Sport Weight

WPI:  15 - 18 (No of wraps around the object is between 15 to 18)
Makes up to 6 or 6.5 stitches per inch.

3 - Light/ Double Knit Weight

WPI:  12 - 14 (No of wraps around the object is between 12 to 14)
Makes up to 5.5 or 6 stitches per inch.

4 - Medium/ Worsted Weight 

WPI:  9 - 11 (No of wraps around the object is between 9 to 11)
Makes up to 4 or 5 stitches per inch.

5 - Bulky Weight Yarn

WPI:  7 - 8 (No of wraps around the object is between 7 to 8)
Makes up to 3 or 3.75 stitches per inch.

6 - Super Bulky Yarn

WPI:  5 - 6 (No of wraps around the object is between 5 to 6)
Makes up to 1.5 or 3 stitches per inch.

7 - Jumbo Yarn

WPI:  0 - 4 (No of wraps around the object is between 0 to 4)

Thicker yarns work quickly than the thinner ones. You can even buy WPI tool kit from

I hope this piece of write up was helpful and will come handy in future. So, pin it and share it.

1 comment:

  1. With the information you have shared, it is very useful for my work. I will regularly visit your blog to learn more new information. Thank you.
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