Crochet Yarn Weights — Complete Guide (Lace to Jumbo)
Every yarn weight category, the hook size to pair it with, what it's best for, and how the US Craft Yarn Council numbers map to UK terminology.
Crochet yarn weights run from 0 (lace) through 7 (jumbo), with 4 (worsted/medium) being the most common for amigurumi, blankets, and beginner projects. Each weight pairs with a recommended hook size — worsted typically uses a 5–5.5mm (H–I) hook, DK uses 4mm (G), and lace uses 1.5–2.25mm (steel). The Craft Yarn Council ball-band number tells you the weight category at a glance; gauge (stitches per 4 inches) is the most reliable way to verify.
| Weight # | Name | US term | UK equivalent | Hook size | Stitches per 4" | Best for |
|---|---|---|---|---|---|---|
| 0 | Lace | Fingering / Crochet Thread | Cobweb / 2-ply | 1.5–2.25mm | 32–42 sc | Doilies, fine lace, thread crochet |
| 1 | Super Fine | Sock / Fingering | 4-ply | 2.25–3.5mm | 21–32 sc | Socks, lightweight shawls, baby items |
| 2 | Fine | Sport / Baby | Sport | 3.5–4.5mm | 16–20 sc | Lightweight garments, baby blankets |
| 3 | Light | DK / Light Worsted | DK | 4–5.5mm | 12–17 sc | Garments, baby items, detailed amigurumi |
| 4 | Medium | Worsted / Aran | Aran | 5.5–6.5mm | 11–14 sc | Most amigurumi, blankets, hats, scarves |
| 5 | Bulky | Chunky / Craft / Rug | Chunky | 6.5–9mm | 8–11 sc | Quick-make blankets, scarves, baskets |
| 6 | Super Bulky | Super Bulky / Roving | Super Chunky | 9–15mm | 7–9 sc | Cozy throws, bowls, statement pieces |
| 7 | Jumbo | Jumbo / Roving | — | 15mm+ | 6 sc or fewer | Arm crochet, rugs, oversized accents |
How to read a yarn label
Look for a number inside a yarn-skein icon on the ball band — that's the Craft Yarn Council weight category (0–7). Below the number you'll usually see recommended hook size and gauge in stitches per 4 inches (10cm). When in doubt, the gauge is the truest signal: two yarns with different label numbers but the same gauge will substitute cleanly.
Yardage matters more than weight in grams — patterns specify yardage so colour-changing or substituting brands stays predictable. A 100g ball of worsted has roughly 200 yards (180m); double it for similar coverage in DK.
Substitutions that work
You can usually go one weight up or down from the pattern's recommendation if you adjust hook size to match your gauge. Worsted → DK with a slightly smaller hook for amigurumi gives a tighter, more polished surface. Worsted → bulky for blankets makes the project finish twice as fast.
Don't substitute across more than one weight unless the pattern specifically allows it — gauge differences compound and the finished size will be off.
Fibers within each weight
Within any weight category you'll see cotton, acrylic, wool, blends, and novelty fibers. Cotton shows stitch definition crisply (great for amigurumi), holds shape, and is machine-washable. Acrylic is budget-friendly, easy-care, and forgiving — the standard beginner choice. Wool blocks beautifully but needs hand-washing. Cotton-acrylic blends split the difference and are popular for baby items.
Common questions
What is the most common crochet yarn weight?
Worsted weight (#4) is the most common — used for the majority of amigurumi, blankets, hats, and beginner patterns. It pairs with a 5mm or 5.5mm hook and gives 11–14 single crochets per 4 inches.
Which yarn weight is best for amigurumi?
Worsted weight (#4) cotton is the standard for amigurumi because it shows stitch definition cleanly and holds its shape when stuffed. DK weight (#3) gives finer, more detailed amigurumi — used for keychain-sized makes.
What hook size for worsted yarn?
A 5mm or 5.5mm (US H or I) hook is the standard for worsted weight. For amigurumi, drop to a 4–4.5mm hook so the fabric is tight enough that stuffing doesn't show through.
Is DK the same as light worsted?
DK and light worsted are close but not identical. Both are weight #3, but light worsted is slightly thicker. They usually substitute cleanly with a hook-size tweak.
What's the difference between worsted and aran?
In US terminology worsted and aran are both weight #4 and largely interchangeable. In UK terminology, aran specifically means the heavier end of the medium category — closer to a US heavy-worsted.
Can I substitute one yarn weight for another?
Yes, within reason. Up or down by one weight category usually works if you adjust hook size and check gauge. Skipping two categories changes the finished size and drape too much for most patterns.
Patterns to make
Free patterns that put this guide to work: