crochetCrochet yarn weights explained
The number on the yarn label describes a thickness category. It does not describe the weight of the ball.
In this guide
Read categories 0 through 7Ball weight and yarn weight are differentFiber and construction change the fabricWhen the label is missingRead categories 0 through 7
The Craft Yarn Council groups yarn from 0 Lace through 7 Jumbo. Names such as DK, worsted and bulky describe common families within those categories. Regional names overlap; use the category, label gauge and actual swatch together.
The hook and single-crochet gauge ranges in the table below are guidelines. A pattern can deliberately choose a hook outside the range to make a dense or open fabric. Crochet gauge is not the knitting gauge printed elsewhere on the label.
On a narrow screen, scroll the table sideways to read all columns.
| Category | Common names | Hook guidance (mm) | Stitches per 10 cm |
|---|---|---|---|
| 0 · Lace | fingering, 10-count crochet thread | steel 1.4-1.6 or regular 2.25 | 32-42 (difficult to generalize for open lace) |
| 1 · Super Fine | sock, fingering, baby | 2.25-3.5 | 21-32 |
| 2 · Fine | sport, baby | 3.5-4.5 | 16-20 |
| 3 · Light | DK, light worsted | 4.5-5.5 | 12-17 |
| 4 · Medium | worsted, afghan, aran | 5.5-6.5 | 11-14 |
| 5 · Bulky | chunky, craft, rug | 6.5-9 | 8-11 |
| 6 · Super Bulky | super bulky, roving | 9-15 | 7-9 |
| 7 · Jumbo | jumbo, roving | 15 or larger | 6 or fewer |
Ball weight and yarn weight are different
A 100 g ball can hold thin or thick yarn. “Yarn weight 4” describes a thickness category; “100 g” describes the amount in the package. The length per ball tells you how much yarn you can actually crochet with.
For substitution, compare meters per gram as a useful clue, not a thickness measurement. Fiber density and yarn construction affect the result. Two yarns can have similar meters per gram yet behave differently after washing.
Fiber and construction change the fabric
Cotton, wool blends and acrylic do not have interchangeable elasticity, surface texture or care. Plied smooth yarn usually makes the individual stitch easier to recognize than a fluffy or chenille surface. The project determines which effect is useful.
Compare exact variants. Lion Brand 24/7 Cotton DK and 24/7 Cotton worsted are different products, and sparkle variants can change fiber composition and put-up. A family name is not enough for a matching quantity calculation.
When the label is missing
A wraps-per-inch measurement can help narrow an unknown yarn, but it is sensitive to how tightly you wrap and to yarn texture. Wrap strands side by side without stretching or leaving gaps. Treat the result as a clue, then swatch.
If you do not know the fiber or care, do not assume the yarn tolerates steam or machine drying. Make a small sample and test the intended care. For a fitted pattern or a gift requiring predictable washing, a known yarn label is a better starting point.