Reference
Yarn weights, from lace to jumbo
Yarn weight means thickness, not how much the ball weighs — which is the first thing worth clearing up on a yarn aisle. These are the eight standard categories, the names each one goes by, the hooks they suit, and how to swap one yarn for another without ruining a project.
The eight standard weights
The numbers come from the Craft Yarn Council and appear on many yarn labels inside a small skein symbol. The hook ranges are their crochet recommendations — a starting point, not a rule.
| No. | Category | Also called | Hook range | Typical projects |
|---|---|---|---|---|
| 0 | Lace | Fingering (10-count crochet thread), Cobweb, Thread | Steel 1.6–1.4 mm, or a regular 2.25 mm hook | Doilies, fine shawls, thread lace. |
| 1 | Super Fine | Sock, Fingering, Baby | 2.25–3.5 mm | Socks, lightweight shawls, fine baby garments. |
| 2 | Fine | Sport, Baby | 3.5–4.5 mm | Baby clothes, light garments, small toys. |
| 3 | Light | DK, Light worsted | 4.5–5.5 mm | Garments, blankets, amigurumi with clean stitch definition. |
| 4 | Medium | Worsted, Afghan, Aran | 5.5–6.5 mm | Blankets, hats, bags, most beginner patterns. |
| 5 | Bulky | Chunky, Craft, Rug | 6.5–9 mm | Quick blankets, baskets, winter accessories. |
| 6 | Super Bulky | Super bulky, Super chunky, Roving | 9–15 mm | Throws, floor cushions, oversized scarves. |
| 7 | Jumbo | Jumbo, Roving | 15 mm and larger | Rugs, baskets, statement blankets. |
What each weight is like to work with
- 0 · LaceSteel 1.6–1.4 mm, or a regular 2.25 mm hook
- The only category the Council splits in two: steel hooks of 1.6–1.4 mm, or an ordinary 2.25 mm hook. Steel numbering runs the opposite way to ordinary hooks — a higher steel number is a finer hook.
- 1 · Super Fine2.25–3.5 mm
- Slow to work up, but it gives the most detail — small amigurumi faces read much more clearly at this thickness.
- 2 · Fine3.5–4.5 mm
- A good middle ground when worsted feels bulky and fingering feels endless.
- 3 · Light4.5–5.5 mm
- DK is the default for much of Europe and a very common amigurumi choice, usually with a hook a size or two smaller than the label suggests.
- 4 · Medium5.5–6.5 mm
- The most widely available weight, and the easiest to see your stitches in while you are learning.
- 5 · Bulky6.5–9 mm
- Works up fast, which is satisfying — but it hides fine shaping, so it flatters simple stitch patterns most.
- 6 · Super Bulky9–15 mm
- Heavy enough that a large piece can sag under its own weight; worth accounting for in anything that hangs.
- 7 · Jumbo15 mm and larger
- The Council sets no upper limit here — the recommendation is simply 15 mm and larger. Often worked with hands or arm-sized hooks. Stitch counts are small, so a miscount changes the shape dramatically.
Substituting one yarn for another
Most patterns can be worked in a different yarn than the one they name. These are the checks worth doing before you start rather than halfway through.
- Match the weight number first — a 4 for a 4 — then check the yardage per ball rather than the gram weight.
- Crochet a gauge swatch in the stitch the pattern uses; a substitute that matches on the label can still work up at a different size.
- Consider fibre, not just thickness: cotton has little give and shows stitch definition, wool blocks and stretches, acrylic keeps its shape and is easy to wash.
- For toys, prefer a yarn that holds a tight fabric, so stuffing cannot show through the stitches.
Hook sizes for each weight are in the hook size guide, including why the same hook carries three different names.
Fibre matters as much as thickness
Two yarns can share a weight number and behave nothing alike. Cotton has almost no stretch, holds its shape and shows stitch definition crisply — good for baskets, bags and amigurumi, less forgiving of uneven tension. Wool has memory and bounce, blocks into shape, and hides small inconsistencies. Acrylic is hard-wearing and machine washable, which is often the deciding factor for anything a child will handle.
For toys, fibre choice is also a safety consideration: a fabric tight enough that stuffing cannot escape matters more than the exact yarn, and a washable fibre is worth choosing for anything that will be slept with.
Patterns from the shop
Each pattern lists the yarn it was designed for, so you can match it to what you have.
