Yarn weights
Yarn Weights Explained: Needle Size, Hook Size and Gauge for All 8 CYC Weights
Yarn weight is the thickness of the strand, not the weight of the ball. The Craft Yarn Council groups yarn into eight categories, from 0 lace to 7 jumbo. Worsted, category 4, knits at 16 to 20 stitches per 4 inches on 4.5 to 5.5 mm needles, and heavier categories need fewer stitches and bigger tools.
| CYC | Weight | Other names | WPI | Knit gauge per 4 in | Needles | Crochet gauge per 4 in | Hooks | Yards per 100 g |
|---|---|---|---|---|---|---|---|---|
| 0 | Lace | Fingering (CYC type), 10-count crochet thread, Cobweb, Light fingering | 30 to 40 or more | 33 to 40 | 1.5 to 2.25 mm (US 000 to 1) | 32 to 42 | 1.4 to 2.25 mm (Steel 8 to B-1) | 600 or more |
| 1 | Super Fine | Sock, Fingering, Baby | 14 to 30 | 27 to 32 | 2.25 to 3.25 mm (US 1 to 3) | 21 to 32 | 2.25 to 3.5 mm (B-1 to E-4) | 380 to 600 |
| 2 | Fine | Sport, Baby | 12 to 18 | 23 to 26 | 3.25 to 3.75 mm (US 3 to 5) | 16 to 20 | 3.5 to 4.5 mm (E-4 to size 7) | 300 to 380 |
| 3 | Light | DK, Light Worsted | 11 to 15 | 21 to 24 | 3.75 to 4.5 mm (US 5 to 7) | 12 to 17 | 4.5 to 5.5 mm (size 7 to I-9) | 230 to 300 |
| 4 | Medium | Worsted, Afghan, Aran | 9 to 12 | 16 to 20 | 4.5 to 5.5 mm (US 7 to 9) | 11 to 14 | 5.5 to 6.5 mm (I-9 to K-10.5) | 170 to 230 |
| 5 | Bulky | Chunky, Craft, Rug | 6 to 9 | 12 to 15 | 5.5 to 8 mm (US 9 to 11) | 8 to 11 | 6.5 to 9 mm (K-10.5 to M-13) | 100 to 170 |
| 6 | Super Bulky | Super Bulky, Roving | 5 to 6 | 7 to 11 | 8 to 12.75 mm (US 11 to 17) | 7 to 9 | 9 to 15 mm (M-13 to Q) | under 100 |
| 7 | Jumbo | Jumbo, Roving | 1 to 4 | 6 or fewer | 12.75 mm (US 17) and larger | 6 or fewer | 15 mm (Q) and larger | Not published |
Knit gauge is stockinette stitches per 4 inches. Crochet gauge is single crochet per 4 inches, except lace, which CYC gives in double crochet. Needle and hook sizes are the most commonly used sizes for each category, not rules. Yards per 100 grams come from retailer charts rather than CYC, and fiber content changes them a lot. To swap one yarn for another, try the yarn substitution calculator, see how much yarn each project takes, or read how to choose yarn weight.
Researched from manufacturer specifications, owner manuals and verified owner reviews, not hands-on testing, and not professional advice. As an Amazon Associate, Cozy Stitchery earns from qualifying purchases.