Measuring Wraps Per Inch (With Downloadable PDF!)

Using the Wraps Per Inch Gauge

To measure the thickness of your yarn, wrap approximately 1” of your yarn around a ruler or dowel and then match up the wraps with the gauge below. If you are measuring a very fine yarn, wrap and measure per 5 wraps. Wrap your yarn snugly but not tight; do not stretch the yarn.

Note that “wraps per inch” (WPI) is an approximate guide to yarn size and may vary widely, depending on many factors, including how tightly the yarn is wound, how much length is wound, and how closely packed the yarn is. Also note that unfinished yarn will typically “bloom” when washed, effectively increasing the diameter of the yarn and decreasing the number of wraps per inch.

Using the Wraps Per Inch Reference Chart

This chart provides a rough target WPI for singles spun for the purpose of making plied yarns. These numbers come from a variety of sources, each with a different method of calculation. Your results may vary, depending on your spinning fibre.

For the most consistent results, spin samples and finish your yarn, recording your WPI in unfinished singles, unfinished plied yarn, and also in your finished plied yarn. Use this chart simply as a starting point for your spinning.

Spinning Gauge Tool

You can download the PDF version of the WPI gauge above, but SweetGeorgia also designed a beautiful cherry wood spinning gauge that measures both twist and wraps per inch (1/2″ and 1″ notches), and it can be used as a weaver’s sett gauge or spinner’s yarn gauge.

WPI Tool
Sweet Georgia cherry wood spinning gauge

More About Felicia Lo

Do you have questions about Measuring Wraps Per Inch (WPI)?

Join Our Community!

  • At the School of SweetGeorgia, we’ve built a vibrant and welcoming community of fibre-loving makers, passionate instructors, and dedicated staff. Whether you’re looking for guidance on a new technique or just need a little creative encouragement, we’re here to support you every step of the way.
  • Not yet a member of the School? We invite you to come and see what it is all about! Use the code: EXPLORETHESCHOOL to save 15% on an All-Access monthly membership!
  • We welcome you to join us in our SweetGeorgia Community. This is where we share projects that inspire, have fibre-filled conversations, host make-alongs, and participate in a variety of virtual meetings! We discuss all things knitting, crocheting, spinning, weaving, machine knitting, and more! 
  • Want to stay in the loop? Subscribe to our newsletter! It’s a simple way to stay updated on what’s new at SweetGeorgia and the School of SweetGeorgia, catch up on the latest articles, watch new SweetGeorgia YouTube videos, and be a part of our community without any pressure to post. We value your presence, no matter how you choose to connect with us!

Original publication: August 20th, 2018; Refreshed November 11th, 2025

The post Measuring Wraps Per Inch (With Downloadable PDF!) appeared first on SweetGeorgia Yarns.



Comments

Popular posts from this blog

Crocheting Granny Squares for the Jethro Cardigan

Joining Crochet Granny Squares – It’s Easier Than I Imagined!

What is a Diz and Why Do You Need One?