Yarn Weights: Here's What You Need to Know


Aran? Worsted? Fingering? Figuring out yarn weights can feel like learning a whole new language. You can thank the Craft Yarn Council for that: they're the folks who determine how yarns are categorized and labeled.

It starts with a numbered system based on thickness, going from 0 (super skinny) to 7 (the thickest yarn). And these numbers have commonly used names associated with them, like "lace" or "bulky." Easy enough. But within those numbered categories are subsets (with their own names!) that make things a little more confusing. For example, # 4 medium yarns include both worsted and Aran weights.

Stay with us here — there's a reason for these ranges. Each yarn is measured by the number of wraps per inch , and each numbered category includes a range of wraps. To complicate things further, some patterns will call out the weight of yarn needed by the number (like "#4 medium"), and some by the sub-category name (like "worsted").

In other words, the more backup info you have to help you understand your pattern's requirements, the better. We're laying it all out here, so you'll be ready when questions pop up.

Pro Tip

Quick shout out to the mighty gauge swatch : the finished size of your project depends on yarn weight, needle size AND your own personal knitting tension. So for projects where size matters, you've really gotta start with a swatch.

0: Lace

Shop Lace Yarns

Types of Yarns

  • Crochet thread: Usually cotton, you'll find this super fine thread sold in balls as opposed to hanks or skeins.
  • Fingering: Fingering yarn can be teeny tiny, but be aware that some yarn labeled "fingering" also falls into the #1 weight, too. So remember to knit a gauge swatch to make sure you're getting the size you need!

Types of Projects

Lace shawls, doilies and other super delicate projects are made with this yarn.

1: Super Fine

Shop Fingering Yarns

Types of Yarns

  • Sock: Socks get their own special yarn, usually with nylon or some other sturdy fiber worked in with the wool to make it more durable. Alas, calling something a sock yarn doesn't guarantee it's a specific thickness, so read your yarn label, and always swatch.
  • Fingering: You'll see lots of yarn labeled as 'fingering,' and it can really run the gamut in terms of how it's spun, what the fiber content is and even yarn weight (it also falls in the lace category above).
  • Baby: Baby yarns can vary greatly in thickness, with the thinnest ending up in this super-fine category. No matter the weight, these yarns are super soft.

Types of Projects

You can probably guess: socks and baby items, as well as airy shawls, scarves and lightweight sweaters.

2: Fine

Shop Sport Yarns

Types of Yarns

  • Sport: Sport yarn is works up slightly faster than super-fine yarns, like fingering, but is still lightweight enough to make great garments.
  • Baby: Yeah, some baby yarn spills into this category, too. Fine baby yarn is a little heavier than its super-fine counterpart, but is still soft as a baby's...you get the idea.

Types of Projects

Sport weight can be great for socks, colorwork sweaters, and other accessories.

3: Light

Shop DK Yarns

Types of Yarns

  • DK: Double-knitting yarn (not to be confused with the double-knitting technique ) is a mid-weight yarn, veering into light territory. It falls in the middle of the spectrum, which makes it a Goldilocks yarn for a lot of projects — "just right."
  • Light-Worsted: This is really just another name for DK weight — you'll see them used interchangeably.

Types of Projects

We're hitting the sweet spot here — you'll find patterns for almost everything that use DK, but we're pretty partial oversized shawls, like the one shown here.

4: Medium

Shop Worsted Yarns

Types of Yarns

  • Worsted: We don't play favorites, but if we did, worsted would be at the top of the list. Most beginners use this yarn for their first projects: it's just the right size to see what you're doing, and not so big (ahem, bulky) that it's hard to wrangle. The word "worsted" can also refer to a particular spinning method , so don't be confused if you find a "worsted fingering" out in the wild.
  • Aran: This is code for "like worsted, but a little heavier."

Types of Projects

We love worsted for basically everything: think slipper socks, sweaters, hats and everything in between.

5: Bulky

Shop Bulky Yarns

Types of Yarns

  • Chunky: The terms "chunky" and "bulky" are often used interchangeably, which can make substituting yarns tricky. Pay attention to gauge to make sure you're getting what you need.
  • Rug: This is sturdy yarn, used for rug hooking more than knitting or crocheting.

Types of Projects

Anything you want to knit quick: hats, scarves, even sweaters and home dec projects can work.

6: Super Bulky

Shop Super Bulky Yarns

Types of Yarns

  • Super bulky: Also referred to as super-chunky. Word to the wise: working with yarn this thick can be rough on your hands. Make sure you do your stretches !
  • Roving: Roving is single ply, loosely spun wool. It's got a bit of a rustic feel. Don't confuse it with roving used for spinning: that stuff's not yarn yet.

Types of Projects

Heavy scarves, textured cowls and hats, and home dec projects. You can knit sweaters in this, but they're going to be incredibly warm. You've been warned.

7: Jumbo

Types of Yarns

This category is the new kid on the block, and it's super popular with arm knitters. Some rovings also fall into this category. Again, there's a lot of variation in width here, since jumbo serves as a catchall for anything heavier than super bulky.

Types of Projects

Statement scarves, big blankets and cozy pillows . If you're arm knitting, you're probably using this.

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