Yarn weights and their corresponding number refer to the thickness of the yarn. This may seem confusing because you’d think weight refers to a measurement of ounces/grams.
Let me help you understand the system for yarn weights. This yarn weight chart helps you decide, no matter what garment or accessory you’re hoping to create.
Table Of Contents
- The Official Yarn Weights
- Super Fine
- Super Bulky
- Yarn Weight Conversion Chart
What Are The Different Weights Of Yarn?
Here’s a guide to the yarns according to the Craft Yarn Council Standard Yarn Weight System in the United States. Yarns have different thicknesses, otherwise known as the different yarn weight categories.
Here are the yarn standards ordered by number in increasing weight and thickness, 0-7.
- Lace – 0
- Super Fine -1
- Fine – 2
- Light – 3
- Medium – 4
- Bulky – 5
- Super Bulky – 6
- Jumbo – 7
Want the complete subject of yarn weights? I’ve covered them in separate supporting articles. First, I go into more depth explaining lace weight yarn. For a summary of them all, read on.
Checking the right Yarn weight for a knitted project is important. The thickness determines the dimensions.
Number #0, Lace weight is the lightest weight of yarn and the thinnest type of yarn of the different categories.
Lace weight yarns are used in lace knitting patterns, like shawls and scarf lace patterns. Or if you’re feeling adventurous, delicate baby items.
- US Knitting Needle Size – 000 to 1
- US Recommended Crochet Hook Size – Steel 6, 7, 8 or B-1
- United Kingdom – 1 Ply
- Australia/NZ – 2 Ply
- AKA – Thread, cobweb, light fingering yarn, crochet thread
- Wraps Per Inch (WPI) – 30 – 40+
Number #1 on the chart, Super Fine yarn, includes sock and fingering yarn. Also used for shawls, hats, baby garments, and mittens, these yarn weight types are thicker than lace.
Want your stitches to be fine? This is the weight to choose. It’s commonly used for sock making. People with time could make a sweater knit from super fine yarn. The results are gorgeous!
- US Knitting Needle Size – 1 to 3
- US Recommended Crochet Hook Size – B-1 to E-4
- UK – 3 Ply and 4 Ply
- AUS/NZ/South Africa – 3 Ply and 4-ply yarn
- AKA – Sock weight yarn, fingering weight yarn, sock fingering yarn
- Wraps Per Inch (WPI) – 14 – 30
This is the number 2 yarn weight category in the chart of yarn weight numbers. Fine yarn (confused with light yarn, which is thicker) includes sport weight yarns and baby weight yarn.
A great all-rounder yarn and the right choice for projects like hats, socks, scarves, cardigans, baby clothes, and sweaters.
- US Knitting Needle Size – 3 to 5
- US Recommended Crochet Hook Size – E-4 to 7
- UK – 5 Ply
- AUS/NZ – 5 Ply
- AKA – Sport weight yarn, Baby weight yarn
- Wraps Per Inch (WPI) – 12 – 18
Number #3 on the chart, DK weight (this stands for double knit), and light worsted yarns are within this category. Light weight yarn is great for sock knitting.
- US Recommended Knitting Needle Size – 5 to 7
- US Recommended Crochet Hook Size – 7 to I-9
- The UK – DK
- AUS/NZ – 8 Ply
- AKA – DK weight yarn, light worsted weight yarn
- Wraps Per Inch (WPI) – 11 – 15
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Number #4, medium weight yarn includes worsted yarn and Aran yarn. It’s popular with beginner knitters and is suitable for many knitted projects. You find many free patterns for this!
- US Knitting Needles Sizes – 7 to 9
- US Recommended Crochet Hook Size – I-9 to K-10 1⁄2
- UK – Worsted weight yarns, Aran
- AUS/NZ – 10 Ply
- AKA – Worsted weight yarn, Aran weight yarn
- Wraps Per Inch (WPI) – 9 – 12
Number #5 on the chart, chunky yarns and rug yarns fall into this category. Excellent for knitting up a project quickly. As the name suggests, the result is bulky but makes for a cozy scarf or cowl.
- US Knitting Needle Size – 9 to 11
- US Recommended Crochet Hook Size – K-10 1⁄2 to M-13
- UK – Bulky or Chunky yarn
- AUS/NZ – 12 Ply
- AKA – Bulky weight yarn, chunky weight yarn, rug yarn
- Wraps Per Inch (WPI) – 6 – 9
Number #6 on the chart, Super bulky yarns make knitting up a hat super fast! These heavier weight yarns are warm and have a bulky look, hence the name super bulky yarn.
- US Knitting Needle Size – 11 to 17
- US Recommended Crochet Hook Size – M-13 to Q
- UK – Super Chunky
- AUS/NZ – 16 Ply +
- AKA – Roving yarn
- Wraps Per Inch (WPI) – 5 – 6
Number #7 on the chart, the Jumbo category, is a relative newcomer to the Craft Yarn Council Chart. Jumbo and Roving yarns fall in this category.
This thicker yarn is popular for arm knitting scarves, blankets, and home décor.
- US Knitting Needle Size – 17 and larger
- US Recommended Crochet Hook Size – Q and larger
- The UK – Jumbo
- AUS/NZ – Jumbo
- AKA – Roving yarn
- Wraps Per Inch (WPI) – 1 – 4
Yarn Weight Comparison Chart
Want a yarn weight conversion chart explaining yarn weights and category names? See the following chart of knitting yarns.
Want a visual representation of the different thicknesses? Watch the video below.
Here is a yarn weights FAQ.
What Does Ply Mean?
When you see the terms 2 ply, 4 ply, 8 ply,10 ply, 12 ply it means 2 or more single strands are twisted together. To ply yarn, individual singles are spun together.
The twist is worked in the opposite direction from how they spun the singles. As a general rule, the number relating to ply doesn’t determine how thick the yarn is.
You can have a bulky two-ply yarn or a thin four-ply yarn, depending on the thickness of the single strands.
What Determines The Weight Of Yarn?
This is confusing, but the physical weight (measured in ounces or grams usually) has nothing to do with the yarn weight! Instead, it’s determined by the width of the yarn strand. This is measured by a system called WPI, (Wraps per inch)
What Is WPI?
Wraps per Inch (WPI) It’s a method of determining the weight of the yarn. To do it, take a strand of fiber and wrap it around a ruler until one inch is completely covered.
Count the number of wraps, and it’ll tell you what you’re working with! This is an excellent way to tell what weight a yarn is when you’ve lost the label.
Ply VS WPI
- Ply – a measurement of how many strands make up one strand of yarn
- WPI – a measurement of how many times a yarn strand wraps around a width of one inch to determine yarn weight
Are Yarns In The Same Category The Same Weight?
The answer is no. Not all are the same thickness, and sometimes it changes between yarn manufacturers. For example, yarns labeled with the Number 4 (Medium Weight) may not all be the same thickness.
However, most yarns in the same category should have similar gauge ranges. Variables that affect the overall thickness include:
- Materials – wool is thicker than cotton, for example
- Twist – a tightly twisted yarn is thinner than one loosely twisted
- Spinning Method – hand-spun yarns vary in thickness
How Do I Tell What Weight My Yarn Is?
Here’s a helpful video tutorial on how to tell your yarn’s weight. It’s all about Wraps per Inch.
If you get stuck, ask someone at your local craft store for help. They’ll be knowledgeable on things like yarn labels, the suggested needle size and the gauge range.
How Do You Substitute Yarn Weights?
If you’re substituting one yarn weight for another in a pattern, ensure the new yarn is close to the recommended gauge.
To test it, make a gauge swatch before starting the main project. Remember, yarn weight matters for your final project!
Which and how much yarn you use has a big impact on the result. Have enough yarn for your knit or crochet patterns! For example, if a pattern calls for DK yarn and you want to use worsted, choose a worsted with a gauge similar to the DK.
How Do You Read The Weight Of Yarn On A Label?
Every yarn has a label with helpful information on them, and this usually includes the weight number and weight category. Sometimes they’ll have a symbol on the yarn label.
Different countries sometimes have varying names for the same weight. To learn those terms, watch this video.
It will be super helpful for understanding the different weight names.
Hope you found this guide to the different yarn weights helpful! Get out there and make something with any yarn size! Have fun with your knitting or crochet projects.
If you have questions or are struggling with understanding yarn weights, leave them in the comments. (Your email address is never published.)
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- How to Measure Wraps Per Inch (WPI) | Welcome to the Craft Yarn Council. “How to Measure Wraps Per Inch (WPI) | Welcome to the Craft Yarn Council.” Accessed October 2, 2022. https://www.craftyarncouncil.com/standards/how-measure-wraps-inch-wpi.
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