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All About Yarn Weight and Why It Matters

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One of the key aspects of making perfect crochet and knitting projects includes understanding its materials: the YARN. In this yarn guide, we’ll break down the basics of yarn weight, navigate through the different yarn categories, and learn how to choose the right yarn for your project. 

Explore & understand 8 yarn weights: from lace to worsted, bulky to jumbo, for crochet & knitting. With yarn weight chart & conversion, WPI & many useful tips.

In this comprehensive guide, we’ll unravel the world of yarn weights, exploring topics like yarn category, wraps per inch, and gauge. Discover tips for choosing the right yarn for a project, substituting yarn in patterns, and avoiding mistakes during the selection process.

As a bonus, you’ll find yarn recommendations, free patterns for each yarn category, and common FAQs. Let’s get started!

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Why is Yarn Weight Important?

Choosing the right yarn weight is important for achieving the CORRECT SIZE in your projects, especially when making wearable items like hats, sweaters, tops, bralettes, and more.

Besides, each yarn weight has its characteristics, influencing the drape, stitch definition, fit, and appearance of a finished piece. Finer yarns create delicate, lightweight pieces with intricate details, while bulkier yarns result in warmer, more cozy items.

How Yarn Weight Is Determined?

As mentioned earlier, yarn weight is a measurement of the thickness of the yarn, from thinner and finer yarn to thick and bulky yarn.

Explore & understand 8 yarn weights: from lace to worsted, bulky to jumbo, for crochet & knitting. With yarn weight chart & conversion, WPI & many useful tips.

What is Yarn Standard?

In order to standardize the yarn weight across the yarn industry, the Craft Yarn Council (CYC) has categorized yarn into eight categories based on thickness.

It is a guideline to help you choose the right yarn for your project, with useful information such as the yarn’s corresponding gauge range, crochet hook, and knitting needle sizes. 

Yarn Weight Category

This overview covers different categories and types of yarn, including fabric texture and project suggestions. It also provides recommended hook and needle sizes for each yarn type.

This overview covers different categories and types of yarn, including fabric texture and project suggestions. It also provides recommended hook and needle sizes for each yarn type.

Please refer to CYC’s Standard Yarn Weight System for the detailed chart.

Laceweight yarns are the lightest weight of yarn, producing an airy, lacy, and drapey fabric that is wearable even on warmer days.

0 Lace (Crochet thread)

Laceweight yarns are the finest and lightest weight of yarn, producing an airy, lacy, and drapey fabric that is wearable even on warmer days.

Ideal for: Doilies, beach cover-ups, cowls, and shawls

Recommended crochet hook size: US Steel hook (6, 7, 8) / 1.6mm to 1.4mm (Regular 2.25mm)

Recommended needle size: US 000-1 / 1.5mm to 2.25mm

Yarn examples:

  1. DMC, Cebelia Crochet Cotton, Ecru, Size 20: This double-mercerized combed cotton promises a smooth and elegant finish, making it a luxurious and durable choice for intricate projects.
  2. Malabrigo, Mechita: Get your hands on this super-soft single-ply fingering weight yarn; great for making lightweight garments with its beautiful hand-dyed colors and amazing drape.

Project Examples:

This shawl offers the perfect blend of elegance and coziness with its asymmetrical design, knitted from the corner to form a triangle with tassels on the corners.

Stormy Sky Shawl

This shawl offers the perfect blend of elegance and coziness with its asymmetrical design, knitted from the corner to form a triangle with tassels on the corners.

Customize your pineapple doily by placing the puff stitches at different rounds of the project, or add colorwork for a unique design. 

Crochet Doily Pattern

Customize your pineapple doily by placing the puff stitches at different rounds of the project, or add colorwork for a unique design. 

Super fine-weight yarn is slightly thicker than lace, making it suitable for lightweight garments and accessories with fine stitch definition.

1 Super Fine (Fingering, Sock, Baby)

Super fine-weight yarn is slightly thicker than lace, making it suitable for lightweight garments and accessories with fine stitch definition.

Ideal for: Socks, shawls, summer tops, bralettes, and cover-ups.

Recommended crochet hook size: US B-1 to E-4 / 2.25mm to 3.5mm

Recommended needle size: US 1 to 3 / 2.25mm to 3.25mm

Yarn examples:

  1. Cascade, Heritage: This luxurious superwash merino wool and nylon blend boasts softness and durability, showing excellent stitch definition.
  2. Patons, Kroy Socks: With its dynamic self-striping hues, this versatile fingering weight yarn adds a playful touch to your sock and accessory projects.

Project examples:

Explore the beauty of broomstick lace with this free scarf pattern; it’s lightweight, breathable, and elegant!

Crochet Lace Scarf Pattern

Explore the beauty of broomstick lace with this free scarf pattern; it’s lightweight, breathable, and elegant!

If you’re up for a challenge, try this two-colored Tunisian crochet pattern, crafted using a lightweight yarn that ensures comfort and easy care.

Ebun Headband Pattern

If you’re up for a challenge, try this two-colored Tunisian crochet pattern, crafted using a lightweight yarn that ensures comfort and easy care.

Fine-weight yarns are great for creating lightweight, breathable items, from garments to accessories, that balance style and comfort.

2 Fine (Sport, Baby)

Fine-weight yarns are great for creating lightweight, breathable items that balance style and comfort, from garments to accessories.

Ideal for: Baby items, lace projects, socks

Recommended crochet hook size: US E-4 to 7 / 3.5mm to 4.5mm

Recommended needle size: US 3 to 5 / 3.25mm to 3.75mm

Yarn examples:

  1. Knit Picks, Shine Sport: This is a smooth and radiant yarn, perfect for making soft and breathable garments with its cotton blend and modal fibers.
  2. Knit Picks, Comfy Sport: This is a super-soft yarn with a blend of cotton and acrylic fibers, ensuring both comfort and durability.

Project examples:

This is a fun and easy way to create adorable miniature fruits, perfect for decoration or play.

Crochet Apple

This is a fun and easy way to create adorable miniature fruits, perfect for decoration or play.

Add a touch of handmade charm to your daily accessories with this small crossbody bag.

Small Crochet Crossbody Bag

Add a touch of handmade charm to your daily accessories with this small crossbody bag.

Lightweight yarns are a step up in terms of thickness, making them ideal for projects requiring a bit more warmth without too much bulk.

3 Light (DK, Light worsted)

Lightweight yarns are a step up in terms of thickness, making them ideal for projects requiring a bit more warmth without too much bulk.

Ideal for: Home decor, clothing, stuffed toys (amigurumi), or accessories

Recommended crochet hook size:  US 7 to I-9 / 4.5mm to 5.5mm

Recommended needle size: US 5 to 7 / 3.75mm to 4.5mm

Yarn examples:

  1. Bernat Softee Baby: This gentle and versatile baby yarn is known for its soft, lightweight feel and easy-care characteristics; it’s also for the little one’s sensitive skin.
  2. Lion Brand, 24/7 Cotton DK: This 100% cotton yarn is versatile, perfect for creating comfortable and breathable garments in various vibrant colors.

Project examples:

Set sail with Craft Passion’s adorable sailor outfit, offering a detailed guide to crafting adorable attire for stuffed toys or your little ones.

Crochet Sailor Bear Pattern

Set sail with Craft Passion’s adorable sailor bear, offering a detailed guide to crafting adorable attire for stuffed toys or your little ones.

Craft personalized gifts for the little ones with this soft, cozy, textured bobble stitch blanket.

Bobble Crochet Baby Blanket (+7 Bonus Sizes)

Craft personalized gifts for the little ones with this soft, cozy, textured bobble stitch blanket.

Medium-weight yarns are the most popular and versatile yarn category, as you can use them for almost any type of project. Also, since they’re the balance between being thick enough yet not too bulky, they’re ideal for beginners.

4 Medium (Worsted, Aran)

Medium-weight yarns are the most popular and versatile yarn category, as you can use them for almost any type of project. Also, since they balance being thick enough yet not too bulky, they’re ideal for beginners.

Ideal for: Stuffed animals, coasters, potholders, bags, and more.

Recommended crochet hook size:  US I-9 to K-10 ½ / 5.5mm to 6.5mm

Recommended needle size: US 7 to 9 / 4.5mm to 5.5mm

Yarn examples:

  1. Red Heart – Super Saver: Here’s a classic medium-weight yarn known for its extensive color range and durability. It’s a go-to choice for many seeking affordability without compromising on quality.
  2. Caron Simply Soft Yarn: Known for its smooth texture and vibrant sheen, this worsted-weight yarn comprises 100% acrylic fibers.

Project examples:

Crochet charming tulips with this free pattern, perfect for adding a touch of springtime element to your indoor space.

Crochet Tulip Free Pattern

Crochet charming tulips with this free pattern, perfect for adding a touch of springtime element to your indoor space.

This comprehensive beanie pattern offers sizes ranging from newborn to adult, making it versatile for all ages and skill levels.

Crochet Beanie: 9 Sizes

This comprehensive beanie pattern offers sizes ranging from newborn to adult, making it versatile for all ages and skill levels.

Bulky-weight yarns are much heavier than medium-weight yarns and are quick to work up. They offer a cozy yet stylish finish, perfect for warm projects.

5 Bulky (Chunky)

Bulky-weight yarns are much heavier than medium-weight yarns and are quick to work up. They offer a cozy yet stylish finish, perfect for warm projects.

Ideal for: Scarves, hats, sweaters, blankets

Recommended crochet hook size: US K-10 ½ to M-13 / 6.5mm to 9mm

Recommended needle size: US 9 – 11 / 5.5mm to 8mm

Yarn examples:

  1. Lion Brand, Scarfie: This yarn boasts a distinctive color gradient and luxurious texture, ideal for cozy scarves and accessories.
  2. Bernat, Velvet: With a range of vibrant colors, this easy-care yarn is perfect for cozy scarves, hats, and blankets.

Project examples:

Enhance your space with this handmade nature-inspired crochet wall hanging.

Crochet Wall Hanging Pattern

Enhance your space with this handmade nature-inspired crochet wall hanging.

Discover how to knit a chic zipper cowl featuring intricate cable designs and stunning ombre effects.

Zipper Cowl Knitting Pattern

Discover how to knit a chic zipper cowl featuring intricate cable designs and stunning ombre effects.

As its name suggests, super bulky yarns make very thick and warm items. They are great for beginners as they produce visible stitches and quick results.

6 Super Bulky (Super Chunky, Roving)

As its name suggests, super bulky yarns make very thick and warm items. They are great for beginners as they produce visible stitches and quick results.

Ideal for: Thick blankets, warm winter accessories, chunky pillows

Recommended crochet hook size: US M-13 to Q / 9mm to 15mm

Recommended needle size: US 11 to 17, 8mm to 12.75mm

Yarn examples:

  1. Bernat, Blanket: Bernat Blanket is a super bulky chenille-style yarn, perfect for cozy blankets and chunky accessories. 
  2. Lion Brand, Hometown: This is a versatile, machine-washable, super bulky yarn. It’s ideal for quick and bold projects.

Project examples:

Elevate your winter accessories with this chunky headband, offering comfort and style.

Chunky Twist Headband

Elevate your winter accessories with this chunky headband, offering comfort and style.

Combine a lace pattern with chunky yarn, and you'll achieve a striking blend of texture and cozy warmth in your project.

Lace Scarf Knitting Pattern

Combine a lace pattern with chunky yarn, and you’ll achieve a striking blend of texture and cozy warmth in your project.

Jumbo weight yarn is the thickest, making it suitable for projects requiring a bold, chunky texture. They work up extremely fast and are usually used for home decor patterns.

7 Jumbo (Roving)

Jumbo weight yarn is the thickest, making it suitable for projects requiring a bold, chunky texture. They work up extremely fast and are usually used for home decor patterns.

Ideal for: Pillows, blankets, and arm-knit projects. 

Recommended crochet hook size: US Q or larger / 15mm or larger

Recommended needle size: US 17 or larger / 12.75mm or larger

Yarn examples:

Change premier yarn (not a popular brand) to Lion Brand, Go For Faux Thick & Quick

  1. Lion Brand, Go For Faux Thick & Quick: This jumbo yarn offers a luxuriously soft and fluffy texture, perfect for adding a touch of warmth and style to your cozy blankets and accessories.
  2. Bernat, Blanket Extra Thick Yarn: This super bulky chenille-style yarn is known for its softness and voluminous texture, creating warm blankets and snuggly accessories. 

Project examples:

This type of yarn makes any project extra soft and squishy, perfect for creating cozy and functional baskets.

Bernat Garter Knit Basket

This type of yarn makes any project extra soft and squishy, perfect for creating cozy and functional baskets.

Indulge in the plush texture and vibrant colors of this yarn as you craft snug blankets perfect for chilly evenings.

Crochet Weighted Blanket

Indulge in this yarn’s plush texture and vibrant colors as you craft snug blankets perfect for chilly evenings.

Yarn Weight Chart & Conversion

CYC CategoryUSWraps Per Inch (WPI)UKAU 
0 LaceLace30-401 ply2 ply
1 Super fineFingering14-302 ply3 ply
2 FineSport12-183 ply3 ply
3 LightDK11-154 ply5 ply
4 MediumWorsted9-12DK8 ply
5 BulkyBulky6-9Aran10 ply
6 Super BulkySuper Bulky5-6Chunky12 ply
7 JumboJumbo/Roving1-4Super Chunky14 ply

What is WPI and How to Measure It

WPI stands for “wraps per inch,” and it’s a measurement used to determine the thickness or diameter of yarn.

If you come across mystery yarn without labels, you can use the WPI method to help you determine the yarn weight. It’s very simple; all you need is a ruler!

How to measure WPI using a ruler:

Grab a ruler and a section of the yarn;

Start at the beginning of the ruler and wrap the yarn snugly around it without overlapping;

Count the number of times the yarn wraps around the ruler or tool within one inch. Each wrap represents one WPI;

Compare the number of wraps per inch to the conversion chart above to determine the yarn category.

How to measure WPI using a ruler:

  1. Grab a ruler and a section of the yarn;
  2. Start at the beginning of the ruler and wrap the yarn snugly around it without overlapping;
  3. Count the number of times the yarn wraps around the ruler or tool within one inch. Each wrap represents one WPI;
  4. Compare the number of wraps per inch to the conversion chart above to determine the yarn category.

You could also purchase a WPI tool to measure the thickness of your yarn. However, I’ve found that the ruler method is more effective and doesn’t cost anything!

What does PLY mean?

Ply is the number of individual strands twisted together to form a single yarn. This determines the yarn’s thickness and texture in a finished project. Yarns with a higher ply count are more durable and provide better stitch definition. A lower ply count results in a softer, more delicate yarn.

Ply is the number of individual strands twisted together to form a single yarn. This determines the yarn's thickness and texture in a finished project. Yarns with a higher ply count are more durable and provide better stitch definition. A lower ply count results in a softer, more delicate yarn.

However, ply can have different meanings depending on the context in which it’s used.

In the UK and Australia, “ply” refers to the thickness or weight of the yarn. For example, 4-ply yarn would typically be a finer-weight yarn. However, this measurement doesn’t directly correlate with the yarn weight chart above.

Common mistakes to avoid when choosing yarn weight:

  1. Ignoring pattern recommendations:
    This can lead to a difference in the size, fit, and drape of the finished project. Unless you have a specific idea in mind, always stick to the original hook/needle size and yarn weight for the best results.
  2. Skipping gauge swatches:
    Making a swatch ensures your project turns out the same as expected, especially for wearable items. Failure to do so can result in unexpected size variations.
  3. Neglecting hand tension:
    Understanding and adjusting your hand tension for different yarn weights is crucial for achieving the desired outcome.

Yarn Weight and Gauge 

In this section, we delve into the bond between yarn weight and gauge, discussing why achieving the correct gauge is important for the success of your project and offering tips on adjusting the gauge when working with different yarn weights.

Getting the correct gauge ensures that your finished project aligns with the pattern's intended size and outlook. It is vital for projects like garments, where precise sizing is essential for a comfortable fit.

How does yarn weight affect the gauge?

Yarn weight is pivotal in determining gauge, which is the number of stitches and rows per inch in a knitted or crocheted fabric.

Thicker yarns typically result in fewer stitches per inch, producing a fabric with a lower stitch count per square inch.

On the contrary, finer yarns result in more stitches per inch, requiring more crochet stitches to achieve the same size as thicker yarns.

In simpler terms, thicker yarn will create a larger piece with the same amount of stitches and rows when compared to thinner yarn.

Why is it important to achieve the correct gauge?

Getting the correct gauge ensures that your finished project aligns with the pattern’s intended size and outlook. It is vital for projects like garments, where precise sizing is essential for a comfortable fit. Stay tuned as we’ll delve into the details of Crochet Tension Gauge in another post.

Choosing the Right Yarn Weight for Your Project

When choosing yarn weight, it is important to consider the nature of your project. Here are a few ways to determine which type of yarn is right for you!

Factors to consider

  • Project type:
    – Intricate projects go best with lightweight yarn like lace and fingering.
    – Chunkier yarns, like worsted-weight yarn or bulky, are for cozy blankets and winter wear. 
  • Stitch pattern:
    – Threadwork or openwork is better paired with fine yarns to showcase its decorative elements.
    – Combining thick yarn with stitches like seed stitch, basketweave, cable stitch, or moss stitch can enhance your project’s overall appearance.
  • Drape:
    – Lightweight yarns have a lovely flow and allow for an elegant drape.
    – A heavy, warm blanket will benefit from the weight and structure provided by a bulky yarn.

FAQ

Here is a quick recap of some of the questions about yarn weights:

1. What is PLY?

Ply refers to the number of strands twisted together to form a yarn. For example, a three-ply yarn comprises three strands of yarn intertwined together. 

2. What yarn weight is recommended for beginners?

For beginners, it’s best to start with medium-weight yarn (worsted), as it offers clear stitch definition and versatility, making it easier to work with for various projects. 

3. How is yarn weight determined?

Yarn weight is determined by its thickness, measured in wraps per inch (WPI), or categorized based on standards set by the Craft Yarn Council, which classifies yarn from lace to jumbo weight. 

4. How to choose a suitable yarn for your project?

Consider your project type, tension gauge, stitch pattern, and desired drape. Also, refer to the pattern’s recommended yarn weight for best results. 

5. How do you choose the correct hook size for your yarn?

Refer to the yarn label or pattern instructions for the recommended hook size. Make a gauge swatch to ensure your hook aligns with the desired tension.

6. Is gauge important?

Yes, gauge is critical in garment-related projects as you must ensure it matches its intended measurements.

7. How do I find a substitute yarn weight?

Match the recommended pattern gauge with the substitute yarn by making a swatch. Adjust the needle or hook size or your tensions accordingly. 

8. How do you determine the yarn weight if they’re not labeled?

Measure the wraps per inch (WPI) using the above method or compare it to the standard yarn weight to estimate the thickness and choose the category accordingly. 

9. Does the yarn weight affect how my project turns out?

Yes! It influences the size, fabric’s drape, texture, and overall appearance. 

10. What are the differences between lace, fingering, sport, worsted, and bulky yarns?

They represent different yarn thickness levels, with lace being the finest and bulky being the thickest. 

11. What yarn weight should I use for blankets?

Worsted weight yarn or bulky weight yarns are best for blankets, offering a balance of warmth and speed for project completion.

12. What yarn weight should I use for amigurumi?

This depends on the desired results and the intended size of the stuffed toy. But generally, sport or worsted weight yarns are used for Amigurumi projects, providing the necessary structure and detailing. 

13. Can I mix different yarn weights in a single project? 

It is possible, but keeping the tension and overall design in mind is important. 

14. What if I need help finding the specific yarn weight in the pattern?

Find a substitute yarn with a similar gauge to ensure your project matches the pattern’s recommended size and appearance. 

What’s next after this Yarn Weight guide?

Dive into the basics of crochet, exploring topics such as crochet hooks and the fundamentals of starting your crochet journey. Our tutorials offer extensive knowledge and detailed insights. There’s a lot to learn, making them valuable resources for both beginners and experienced crafters.

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About Joanne, owner of Made From Yarn

Joanne Loh

~ Founder and Editor ~
Born into a creative family, Joanne Loh has over 40 years of experience in knitting and crocheting. Well-known for her creative approach to yarn crafts, her creations demonstrate a strong dedication to quality and spreading her enthusiasm among the crafting community.
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