CrochetZen yarn guide
Yarn Weights and Fibers Explained
Picking the right yarn changes everything about a project. The weight determines how fast it works up and how warm the result is. The fiber determines how it feels, how it washes, and how it ages. Each guide below gives you the actual numbers: CYC weight category, hook size range, yardage estimates, and specific best uses.
US and UK yarn weight names do not always match. Worsted in the US is close to aran in the UK. DK is the same name in both systems but can vary slightly in thickness between brands. Each page notes the UK equivalent so you can follow patterns from either tradition.
Start with the guides
New to yarn? These plain-English guides cover the concepts behind the reference pages below, from what a skein actually is to swapping one yarn for another.
- Start here
What Is a Skein of Yarn? A Plain-English Guide
A skein of yarn is one unit, or put-up, of yarn. Learn skein vs hank vs cake, how to read a label, and how much yarn your project really needs.
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How to Read a Yarn Label: Every Number, Symbol, and Icon Explained
Learn how to read a yarn label from brand and colorway to dye lot, fiber content, weight, yardage, care symbols, and gauge. Everything on the label explained clearly.
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How to Wash and Block Crochet: A Calm, Complete Guide
Learn how to block crochet using wet blocking, spray blocking, and steam blocking. Plus how to wash finished pieces correctly for every fiber type.
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Yarn Weight Guide: All 8 Categories Explained
A complete yarn weight guide covering all 8 categories from lace to jumbo. Includes a chart with WPI, recommended hook and needle sizes, and the best projects for each weight.
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Crochet Yarn for Beginners: How to Pick Your First Yarn
Crochet yarn for beginners, made simple. Pick a smooth, light worsted yarn, learn what to avoid, how much to buy, and the first project to pair it with.
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Yarn Substitution: How to Swap Yarn in Any Pattern
Yarn substitution made simple: match the weight, swatch for gauge, then check fiber and total yardage. A practical step-by-step from the CrochetZen team.
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Yarn Weights
- CYC 4·UK: Aran
Worsted Weight Yarn
Hook: 5.0 to 6.5 mm (US H/8 to K/10.5)
Worsted weight (CYC 4) is the most popular yarn weight for crochet and knitting, balancing speed, warmth, and ease of working for beginners and experts alike.
Full guide →
- CYC 3·UK: Double Knitting (DK)
DK Weight Yarn
Hook: 3.5 to 4.5 mm (US E/4 to G/7)
DK weight (CYC 3, double knitting) is a light-medium yarn that produces finer fabric than worsted but works up faster than fingering, popular for garments and lightweight accessories.
Full guide →
- CYC 5·UK: Chunky
Bulky Weight Yarn
Hook: 6.5 to 9.0 mm (US K/10.5 to M/N/13)
Bulky weight (CYC 5) yarn works up fast on large hooks and is a favorite for chunky blankets, cozy hats, and beginner projects where quick results build confidence.
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- CYC 5·UK: Chunky
Chunky Yarn
Hook: 6.5 to 9.0 mm (US K/10.5 to M/13)
Chunky yarn (CYC 5) is a thick, fast-working weight that crochets and knits up in a fraction of the time of worsted, ideal for cozy hats, scarves, and quick blankets.
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- CYC 1
Sock Yarn
Hook: 2.25 to 3.5 mm (US B/1 to E/4)
Sock yarn is a fine, hard-wearing yarn, usually a superwash wool and nylon blend in fingering weight, made to survive the friction of a sock and machine washing.
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- CYC 2
Sport Weight Yarn
Hook: 3.5 to 4.5 mm (US E/4 to 7)
Sport weight yarn (CYC 2) sits between fingering and DK, a light yarn that makes soft, fine-gauge baby clothes, lightweight garments, and detailed accessories.
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- CYC 0
Lace Weight Yarn
Hook: 1.5 to 2.25 mm (steel to US B/1)
Lace weight yarn (CYC 0) is the finest yarn, almost thread-like, used for delicate shawls, doilies, and openwork where the holes are the design.
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- CYC 6
Super Bulky Yarn
Hook: 9.0 to 15.0 mm (US M/13 to Q)
Super bulky yarn (CYC 6) is a very thick weight that works up almost instantly, perfect for chunky blankets, cowls, and cold-weather accessories.
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Roving Yarn
Roving is a thick, barely-spun rope of fiber used for arm knitting and giant blankets, prized for its softness and dramatic stitch size.
Full guide →
Yarn Fibers
Fiber
Mohair Yarn
Mohair is a long-staple fiber from the Angora goat, prized for its silky sheen, lightweight warmth, and the halo of fine fibers that bloom around each strand after washing.
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Fiber
Chenille Yarn
Chenille yarn has a soft, velvety pile made from short fibers woven around a core thread, producing a plush, smooth fabric often used for baby items, velvet-look blankets, and stuffed toys.
Full guide →
Fiber
Cotton Yarn
Cotton yarn is a plant-based fiber with excellent stitch definition, zero stretch, and full machine washability, making it the go-to material for dishcloths, summer garments, and crochet bags.
Full guide →
Fiber
Wool Yarn
Wool yarn is a warm, elastic animal fiber that holds its shape, takes dye beautifully, and blocks crisply, making it a favorite for garments, hats, and socks.
Full guide →
Fiber
Acrylic Yarn
Acrylic yarn is an affordable, machine-washable synthetic fiber that comes in every color, making it the practical choice for blankets, beginners, and charity makes.
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Fiber
Alpaca Yarn
Alpaca yarn is a silky, warm animal fiber that is softer and warmer than wool with a beautiful drape, though it has less elasticity and memory.
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Fiber
Cashmere Yarn
Cashmere yarn is a luxury fiber from the cashmere goat, prized for being extraordinarily soft and warm, and best saved for special accessories worn close to the skin.
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