Crochet Yarn Weight Explained

Understanding yarn weight can be a powerful arsenal in your crochet knowledge toolbox. It can help you determine the hook size you’ll need, and your stitch gauge.

yarn weight

When we talked about stitch gauge, we determined how important the weight of the yarn and the size of the hook is to determining how true-to-size your project will turn out. Due to the need for a set of standards for yarn manufacturers, the Craft Yarn Council developed a common system to be used across the industry.

Yarn Weight Standards

The standards created for yarn weight begin at 0 and go all the way up to 7. These are updated as necessary as trends change the yarn industry and we continue to see more thick and beautiful yarn available to us. Below I will discuss the weight ratings, what hook sizes are recommended for crocheting these weights, and what types of yarn this includes.

0 – Lace Weight
Hook Size Range: 1.5 – 2.5 mm (Steel 6, 7, 8 or B-1)
Types of Yarns: Fingering, 10-count crochet thread

1 – Super Fine
Hook Size Range: 2.25 – 3.5 mm (B to E)
Types of Yarns: Fingering, Sock, Baby

2 – Fine
Hook Size Range: 3.5 – 4.5 mm (E to 7)
Type of Yarns: Sport or Baby

3 – Light
Hook Size Range: 4.5 – 5.5 mm (7 to I)
Type of Yarns: DK or Light Worsted

4 – Medium
Hook Size Range: 5.5 – 6.5 mm (I to K)
Type of Yarns: Worsted, Afghan, Aran

5 – Bulky
Hook Size Range: 6.5 – 9 mm (K to M)
Type of Yarns: Chunky, Craft, Rug

6 – Super Bulky
Hook Size Range: 9 – 15 mm (M to Q)
Type of Yarns: Super Bulky or Roving

7 – Jumbo
Hook Size Range: 15 mm and larger (Q and larger)
Type of Yarns: Jumbo or Roving

Figuring Out Your Yarn Weight Without a Label

So, you’ve picked up a skein of yarn at your local farmer’s market and have no idea what size it is? No fear, I’ll teach you how to figure out which category it goes in using the pencil test.

(No, not the same one you used to try and determine the sex of your friend’s baby…)

Grab a standard #2 pencil, your yarn, and some measuring tape. (Go ahead, I’ll wait.)

Back? Great! Let’s figure this out.

Wrap the yarn around the pencil a few times where it is touching, yet not overlapping. Do this until you can measure one-inch on your measuring tape. Count the number of loops on the pencil for one-inch of your yarn.

This method is called WPI, or Wraps per Inch. Crochet Spot has put together the handy-dandy table that I always reference for figuring this out. The one thing that I would note is that with the addition of the Jumbo category of yarn, I’d personally put 4 wraps or less in the Jumbo category.

Yarn Weight Substitutions

What if you’ve picked up an amazing pattern that calls for a certain type of yarn, but it’s been discontinued? (Story. Of. My. Life.) How do you find another yarn to substitute for the weight that was called for?

It’s a bit easier than you might think.

  1. Search the Internet for discontinued yarn, or destash yarn. I like to search eBay, Etsy, or even DBNY to find out-of-stock yarns.
  2. Look at the yarn weight category that the original yarn was in. Can’t find the original yarn? Reference the stitch gauge and the crochet hook size used in the pattern to figure that out.
  3. Examine the fiber used in the pattern and select something similar in the same weight category.
  4. Ensure that the yarn you will select as the substitution has the same amount of yardage needed for your project. (If not, calculate the yarn yardage needed).
  5. When in doubt, ask an expert. Don’t be afraid to visit your local yarn shops, or simply ask someone who has some experience with yarn. They’ll be able to at least give you a few tips you haven’t thought of.

I hope that you’ve learned some useful information today, and that you’ll come back to visit us for more crochet tips and tricks!