Yarn Weight Chart and Guide

Crochet Yarn Weight Chart & Guide for Beginners

If you’ve ever felt confused by yarn weight categories, you’re not alone! Understanding yarn weights is key to successful crochet projects – it affects your project’s size, drape, and texture. This beginner-friendly guide will demystify crochet yarn weights and show you how to use a yarn weight chart with confidence. We’ll explain what yarn weight means (hint: it’s about thickness, not the scale reading), how different weights impact the look and feel of your crochet, and how to choose the right yarn weight for any project. You’ll also find a handy yarn weight comparison table and answers to common questions like “What weight is 4mm yarn?” and “What does 25g yarn mean?” – all focused 100% on crochet.

Want a deeper dive into DK and Worsted yarn? Explore our detailed guides on DK Yarn, Worsted Weight Yarn, or DK vs Worsted Comparison to learn how each behaves in real crochet projects. Let’s get started!

What Is Yarn Weight in Crochet?

Yarn “weight” refers to the thickness of the yarn strand – not how heavy the skein is. In other words, it describes how fine or thick the yarn is, which in turn affects the size and appearance of your stitches. For example, a lace-weight yarn is extremely thin, producing very delicate stitches, while a bulky-weight yarn is thick, making big, chunky stitches. Using the correct yarn weight is important because it ensures your project turns out the right size. If your yarn is too thick or too thin compared to what a pattern calls for, your finished piece could end up larger or smaller than intended.

To make sense of yarn thickness, the Craft Yarn Council (CYC) established a Standard Yarn Weight System with categories numbered 0 through 7. Each category corresponds to a general range of yarn thickness. Lower numbers (0, 1, 2…) are thinner (lightweight yarns), and higher numbers (5, 6, 7) are thicker (bulky yarns). These categories have names like Lace, Fingering, DK (double knitting), Worsted, Bulky, etc., which you’ve likely seen on yarn labels. Most yarn labels will list a yarn weight category number or name. For instance, you might see a symbol with a digit like 4 (Medium) or words like “Worsted” or “DK” on the label – that tells you the yarn’s weight category. If only a name is given without a number, knowing the common category names helps you decode the weight (for example, “aran” yarn is equivalent to a medium #4 weight in the U.S.).

Why does yarn weight matter to crocheters? First, it helps you choose the right hook size and stitch gauge for your project. Patterns are usually written with a specific yarn weight in mind; using the recommended weight makes it easier to meet the pattern’s gauge (stitches per inch) so your project ends up the intended size. Yarn weight also affects the drape and texture of your crochet fabric – we’ll dive into that more below. In short, knowing yarn weight keeps your crochet from turning into an accidental surprise (like a doll blanket that unintentionally becomes a tablecloth, or vice versa!).

Want to go deeper into DK and Worsted yarn? We’ve written full guides on DK Weight Yarn, Worsted Weight Yarn, and a full DK vs Worsted comparison to help you choose the perfect yarn for your next project.

Yarn Weight Categories Explained

Yarn weight categories range from 0 (lace) to 7 (jumbo) – with each step up in number, the yarn strand gets thicker. Category 4 (medium), often called worsted, is a popular all-purpose choice for crochet.

The Craft Yarn Council’s standard yarn weight chart breaks yarns into eight basic categories (numbered 0 through 7). Below is a summary of each category, including common names and the typical crochet hook size range for that weight. Yarn weights are often referred to by these category numbers in the U.S., but you’ll also see traditional names (like “fingering” or “bulky”). For our U.S.-based crocheters, we’ve noted the equivalent terms (and a few UK terms in parentheses) for clarity:

Note: These hook sizes are guidelines for a typical crochet fabric. You can always go up or down a hook size to adjust your stitch tightness, but in general the ranges above produce a balanced fabric for that yarn thickness. Also, some category names differ internationally – for example, a medium #4 yarn is called “aran” in the UK, and #5 bulky is often called “chunky”. The numbering system helps standardize the reference.

How to use this yarn weight chart: If a pattern calls for a #3 Light yarn (DK), you’d look in the chart and see that corresponds to a DK weight yarn, and you’d typically use about a 4.5–5.5 mm (Size 7 to I-9) hook. If you’re substituting yarns, you’d want to choose a yarn in the same category with similar thickness. The chart is also handy for understanding pattern terminology. For instance, if a vintage pattern mentions “4-ply yarn,” you can check and realize that in many cases 4-ply corresponds to a Fine or Light weight (approximately a #2–#3 category) – not to be confused with a #4 Medium weight.

Further Reading & Resources:

Want to make the most out of this yarn weight chart?
Explore these helpful guides to deepen your understanding of yarn types and find the perfect hook for your next project:

• What is DK Weight Yarn?
• What is Worsted Weight Yarn?
• Crochet Hook Size Chart: Match Hooks to Yarn Weights

Yarn Weight and Crochet Drape & Texture

One of the biggest effects of yarn weight is on your fabric’s drape and texture – basically, how stiff or fluid the crochet fabric feels, and how the stitches look. The thickness of the yarn affects the drape of the fabric. Here’s how different yarn weights influence your crochet:

• Lightweight yarns (Categories 0–2) produce finer, delicate fabric with a lot of drape (flexibility). For example, a lace-weight yarn can create an airy, flowing shawl or doily where the stitches look gossamer and thin. These thinner yarns are perfect for lacey patterns or intricate stitch work. The trade-off is that they work up more slowly and the finished piece is lighter and less sturdy. Very fine yarns, like thread, can make intricate lace doilies that hold their shape but still have a delicate drape.
• Medium-weight yarns (Categories 3–4) give a balanced drape – not too floppy, not too stiff. This is one reason yarns like DK (#3) and worsted (#4) are so popular and versatile. They create crochet fabric that has some body and structure but can still move nicely. For example, a worsted-weight yarn (#4) with the appropriate hook can make a sweater or blanket that holds warmth and shape but also feels soft and comfortable. Stitches in this range are clearly visible and defined, which is great for showing off textured stitch patterns. In fact, #4 medium (worsted) yarn is often thought of as an “all-purpose” yarn because you can use it for so many types of projects.
• Bulky and super bulky yarns (Categories 5–7) create thick, warm, and often stiffer fabric. With a chunky yarn, your project works up very quickly and the stitches are huge and squishy. This is fantastic for things like cozy blankets, chunky scarves, or rugs. However, a very thick yarn doesn’t drape much – the fabric tends to be heavy and more rigid. For example, if you tried to crochet a lacy summer cardigan with a super bulky (#6) yarn, it would come out far too thick and stiff to flow or ripple – not the effect you want for lace. On the other hand, super bulky yarn is excellent for something like a sturdy basket or a winter cowl where you want thickness and warmth. Jumbo (#7) yarns are extremely thick (often used for arm-crocheting or special projects) and make very heavy, dense pieces with minimal drape.

In summary: Thinner yarn = lighter, floppier, and more fluid fabric; thicker yarn = bulkier, stiffer, and more solid fabric. Always consider the desired outcome: if you want a garment to drape elegantly (like a shawl or draped cardigan), lean toward a lighter weight yarn and an open stitch pattern. If you want something structured or super warm (like a pot holder, basket, or chunky blanket), a heavier weight yarn is ideal. And remember, you can also adjust drape by changing your hook size: using a larger hook on the same yarn will make stitches looser and fabric more pliable, while a smaller hook makes tighter, sturdier fabric.

Choosing the Right Yarn Weight for Your Project

With so many yarn sizes available, how do you decide which weight is best for your project? Here are some tips and common project pairings to help you choose the perfect yarn weight:

• Follow the Pattern (if you have one): If you’re using a crochet pattern, it will usually specify a yarn weight (or even a specific yarn). Stick with that category for the best results. The designer chose that weight to achieve a certain size and look. For instance, if the pattern calls for #3 Light yarn and you use #5 Bulky instead, your project could turn out much larger and denser than expected. When substituting, choose a yarn in the same weight category and check that the yardage and gauge are similar to the original.
• Consider the Project Type: Different projects tend to pair well with certain yarn weights:
  • Lacy shawls, doilies, or delicate details: Use very fine yarn (lace weight #0 or super fine #1) for that light, airy quality.
  • Socks and lightweight garments (like summer tops or baby clothes): Super fine (#1) or fine (#2) weight yarns are commonly used so the items are thin, comfortable, and have stretch. Fingering weight (super fine) is a go-to for socks and baby booties.
  • Amigurumi and toys: Many amigurumi (crocheted dolls and toys) use a medium (#4) worsted weight cotton or acrylic yarn. A #4 yarn with a slightly smaller hook gives a dense fabric so the stuffing won’t show through. For very small amigurumi, some crafters use DK (#3) or even finer, but worsted #4 is a beginner-friendly choice for most stuffed toys. Looking for the best yarns for toy-making? Don’t miss our guide to the Best Yarn for Amigurumi – covering fiber types, structure, and brands that hold shape beautifully.
  • Blankets and afghans: These can use a range of weights. Worsted (#4) is extremely popular for afghans – it strikes a good balance between not-too-heavy and quick to crochet. Baby blankets often use DK or sport weight (#3 or #2) for a softer, lighter feel. If you want a super plush, quick-make throw, bulky (#5) or super bulky (#6) yarn will create a thick, cozy blanket in no time. Thinking of making granny squares? Check out our Best Yarn for Granny Squares guide to explore yarns that offer color pop, durability, and great stitch definition.
  • Sweaters and wearables: This depends on the style. Many crochet sweaters use #3 Light (DK) or #4 Medium (worsted) yarns, which give a good balance of drape and warmth. A summer sweater or shawl might use a #2 Fine for a lighter feel. Chunky fashion sweaters or ponchos might use #5 Bulky for a trendy oversized look. Just remember, heavier yarn will make a garment warmer and thicker – great for winter, but possibly too heavy for indoor or mild weather wear.
  • Hats, scarves, and mittens: A lot of classic hat and scarf patterns call for worsted weight (#4) yarn – it’s warm and works up to a comfortable thickness. Bulky yarns (#5) are also fantastic for really warm winter accessories or a quick gift (think one-hour scarf with super bulky!). For lighter, slouchy beanies or dressier shawl-scarves, you might go down to a #3 Light.
  • Home décor and rugs: When you need sturdiness, go for bulky or jumbo yarn. For example, a crochet basket or rug often uses #6 super bulky or #7 jumbo yarn (or multiple strands of #4 held together) to get a firm, thick result that holds its shape.
• Match the Yarn to the Hook (and vice versa): If you already have a yarn in mind, ensure you have an appropriate hook for it. The yarn label will usually list a recommended crochet hook size. Using a vastly mismatched hook and yarn can lead to frustration – e.g. trying to crochet a chunky yarn with a tiny steel hook will be very difficult, and using a huge 15 mm hook on skinny sock yarn will feel like knitting with broomsticks on sewing thread! For beginners, a worsted weight (#4) yarn paired with about a 5 mm (H-8) hook is often ideal to start – the yarn isn’t too slippery or tiny, and the hook is comfortable to handle.
• Plan for Drape and Feel: As discussed in the previous section, think about how you want the item to feel. If you want a stiff coaster or hot pad, a medium cotton yarn with a slightly smaller hook (for a dense fabric) might work better than a floppy lightweight yarn. If you want a flowy drape in a scarf, choose a lighter yarn or an open stitch with the given weight.

Finally, if you’re ever unsure, make a small test swatch with the yarn and hook to see if you like the fabric. This is especially helpful if you’re substituting a different yarn weight or designing your own pattern. A gauge swatch will show you if the thickness is working for the size and drape you want, and you can adjust accordingly. Choosing the right yarn weight becomes easier with practice – soon you’ll intuitively know that, say, a cabled beanie will turn out best with a nice #4 worsted wool, or that a delicate lace pattern will shine in a #1 fingering cotton.

How to Determine a Yarn’s Weight (Label Clues & WPI)

Figuring out the weight category of a yarn is usually straightforward if you have the yarn’s label. Here’s how to tell, and what to do if the label is missing:

• Check the Yarn Label: Most yarn labels will explicitly state the yarn’s weight category. Look for a symbol of a skein with a number (0–7) inside it, or a written description like “Category 4 – Medium (Worsted)” somewhere on the label. Sometimes it’s near the gauge information. Many labels in the U.S. use the Craft Yarn Council standard symbols. If the label doesn’t have the number, read the yarn description – terms like lace, fingering, sport, DK, worsted, aran, chunky, super bulky are all indicators of weight. Also check the recommended hook size on the label. For example, if the label suggests a 5.00 mm hook (H-8), you’re likely looking at a worsted/#4 yarn; if it suggests a 2.25 mm hook (B-1), it’s probably a fine or super fine yarn. The gauge swatch info on labels is another clue: a label that says “Gauge: 12 sc = 4″ suggests a bulky yarn (since only 12 single crochets in 4 inches means big stitches), whereas “32 sc = 4″ would imply a very fine yarn.
• Understand Label Weight vs. “Yarn Weight”: Don’t confuse the category of the yarn with the physical weight of the skein. For instance, you might see **“25g” on a yarn label – that 25g refers to the yarn’s actual weight in grams, not its thickness. In other words, 25g is telling you how much yarn is in the ball by weight (25 grams per skein). You often see 25g on small skeins of yarn (common for lace yarns, sock minis, or mohair yarns). It doesn’t mean the yarn is category #0 or anything specific – you have to look at the thickness or category info. A 25g ball could be lace weight (which would be a small, short skein, maybe only ~60 meters) or it could even be a thicker yarn in a mini-skein format. The key is that “yarn weight” in pattern terms refers to thickness, while grams/ounces refer to quantity. So, “What does 25g yarn mean?” It simply means the ball weighs 25 grams. Always check if the label also gives a category number or description to know the yarn’s thickness class.
• Use Wraps-Per-Inch (WPI) for unlabeled yarn: Have a mystery yarn with no label? You can still sleuth out its weight by using the wraps-per-inch method. Wraps per inch (WPI) is a technique where you wrap the yarn around a ruler or pencil and count how many wraps fit in one inch. This gives an approximation of the yarn’s thickness. For example, if you can wrap the yarn ~18 times in one inch, it’s likely a sport or DK yarn; only 9 wraps per inch would indicate a bulky yarn. Here’s how to do it:

1. Grab a ruler (or any flat, straight tool) and your yarn.
2. Wrap the yarn around the ruler snugly (but not stretching it) for a one-inch width, with the wraps touching but not overlapping.
3. Count the wraps that fit within that inch.
4. Compare that number to a WPI chart. (Common reference: Lace: 30+ WPI, Fingering: ~14–30 WPI, Sport: ~12–18, DK: ~11–15, Worsted: ~9–12, Bulky: ~6–9, Super Bulky: <6 wraps per inch.)
5. The range will tell you the category. For instance, ~11 WPI is often a light #3 (DK) yarn, whereas ~7 WPI would be category #5–6 (bulky range).

This method is handy for stash yarn that lost its label or handspun yarn. It’s not 100% precise, but it gives a good ballpark to match your yarn to a standard weight category.

• Compare to a Known Yarn: Another simple trick – if you have a labeled yarn of known weight, lay a strand of the mystery yarn next to a strand of the known yarn. Feel them and look at them. If they’re very close in thickness, you can assume they’re in the same category. This side-by-side comparison can be surprisingly effective for common weights (for example, many of us can recognize a #4 worsted-weight yarn by sight/feel because we use it often).

By using these methods, you can tell the weight of a yarn for crochet projects fairly easily. In short: check the label for category info or hook size, and if that fails, use the wraps-per-inch test or compare to a similar yarn to find out the weight category. Once you know the weight, you can confidently pair the yarn with a suitable hook and pattern.

FAQs About Crochet Yarn Weight

In this section, we answer some frequently asked questions (FAQ) about yarn weights in crochet. These quick answers are great for reference and to clear up common points of confusion:

What weight is 4mm yarn?

In crochet, “4mm yarn” isn’t an official category – 4 mm usually refers to a hook or needle size, not the yarn. If someone says “4 mm yarn,” they likely mean a yarn that works well with a 4.0 mm crochet hook (size G). A 4 mm hook is typically used with a Light (#3) or Medium (#4) weight yarn. In fact, a 4 mm hook is a common size for DK (light worsted) yarn. So, there is no specific “4 mm yarn” weight – instead, look for yarn labeled #3 Light (DK) or #4 Medium (Worsted), as those are in the right thickness range for a 4 mm hook. Always check the yarn label’s suggested hook size; if it says around 4 mm, that yarn will match what you need. Want to explore how different hook sizes pair with yarn weights? Don’t miss our Crochet Hook Size Chart – a quick guide to millimeters, U.S. letter sizes, and project-friendly pairings.

What does 25g yarn mean?

“25g yarn” means the ball of yarn weighs 25 grams. This is simply a measurement of quantity, not the yarn’s thickness or category. Yarns are sold in various ball sizes – common ones include 50g, 100g, 3.5oz, etc. A 25g skein is a smaller skein (for example, luxury yarns or sock minis often come in 25g balls). It does not tell you the yarn weight category. For instance, you could have a 25g ball of lace-weight yarn (which would be a lot of length in a small ball), or a 25g ball of bulky yarn (which would be a shorter length of thick yarn). To find the yarn’s weight category, look on the label for terms like lace, DK, etc., or a number 0–7. The 25g tells you you have a small amount of that yarn (in weight), and you’d often need multiple 25g balls for a project. In summary: 25g is the net weight of the yarn skein, not an indicator of yarn thickness.

How do I tell the weight of yarn for crochet?

To determine a yarn’s weight category, check the label for the standard weight symbol or name. Most yarn labels will have a number (0–7) that corresponds to lace, super fine, fine, light, medium, bulky, etc., or they’ll state a descriptor like “Worsted” or “DK.” That’s the easiest way. If the label is missing or unclear, use the wraps-per-inch (WPI) method – wrap the yarn around a ruler and count how many wraps fit in one inch, then compare that to known standards for each weight (fewer wraps = thicker yarn). You can also judge by the recommended hook size on the label: small hook sizes (2–3 mm) mean the yarn is thin, while large hook sizes (6–10 mm) mean the yarn is thick. In short, read the yarn label for category info, and if you don’t have a label, rely on WPI or comparing the yarn’s thickness to a known yarn to tell its weight.

What is the best weight yarn for crocheting?

There isn’t a single “best” yarn weight for all of crochet – it depends on what you’re making – but a Medium weight (#4, Worsted) yarn is often considered the best all-purpose yarn for crocheters. Worsted weight yarn is very beginner-friendly: it’s easy to see your stitches, not too fine or too bulky, and suitable for a wide range of projects (blankets, scarves, baskets, even some garments). Many learn-to-crochet kits recommend a #4 yarn and a 5 mm H-8 hook to start. That said, the best weight is project-specific. For instance, the best weight for crocheting a lace shawl would be a lightweight yarn, not a #4. But if you’re just starting out or want a versatile yarn stash, you can’t go wrong with a few skeins of worsted weight yarn in your favorite colors. From there, you can branch out to thinner yarns for finer projects or thicker yarns for quick, chunky projects. Think of worsted as the go-to middle ground – a balance of ease and versatility – and then choose other weights as needed for the effect you want.

Final Thoughts on Choosing the Right Yarn Weight

With this knowledge under your belt, you’re ready to tackle any crochet pattern with the right yarn in hand! Yarn weight no longer needs to be perplexing – you now know how to read yarn weight charts, interpret labels, and choose yarns that will give you the drape, texture, and size you intend. Whether you’re dreaming up a lacey wrap in fine yarn or a cozy throw in jumbo yarn, understanding yarn weights will help you get the results you envision. Happy crocheting!

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Check out our Free Crochet Patterns and start your next project with confidence!