Yarn Weight Chart: All 8 Categories, Plainly Explained

“Yarn weight” has nothing to do with how much the ball weighs. It means how thick the strand is, and it is the single most important thing to get right when you substitute one yarn for another.

The confusing part is that every country and every brand has its own name for the same thickness. What Americans call worsted, the British call aran, the Australians call 10-ply, and the label might just say “medium.” They are all the same yarn.

The Craft Yarn Council standardized this into eight numbered categories, 0 through 7. That number is the only label that means the same thing everywhere, and it is usually printed inside a little yarn-skein symbol on the ball band.

The chart

Gauge below is single crochet over 4 inches, which is how crochet gauge is conventionally expressed for yarn weight.

The hook ranges are the manufacturers’ suggestions. They are starting points, not rules — see the section on when to ignore them.

What each weight is actually good for

0 — Lace. Doilies, thread lace, fine edgings. Slow, fiddly, and beautiful. Not a beginner yarn, not because the stitches are harder but because you cannot see what your hands are doing.

1 — Super Fine. Socks, shawls, lightweight baby things. Drapes beautifully. A blanket in this weight is a several-month commitment.

2 — Fine. Baby garments and lightweight tops. A reasonable middle ground if you find worsted too bulky for clothing.

3 — Light (DK). The most useful weight for garments. Enough body to hold its shape, fine enough that a sweater does not look armored. Very popular in Europe.

4 — Medium (worsted). The default. Blankets, hats, scarves, amigurumi, dishcloths. Cheap, available everywhere, comes in every color, and most beginner patterns assume it. Learn on this one.

5 — Bulky. Fast blankets, winter hats, chunky scarves. A satisfying weight when you want something finished this weekend.

6 — Super Bulky. Very fast, very warm, very chunky. Uses a lot of yarn, so it gets expensive quickly on anything blanket-sized.

7 — Jumbo. Giant blankets and floor poufs. More of a project category than a yarn category.

Substituting one yarn for another

You will do this constantly, because the specific yarn a pattern calls for is often discontinued or unavailable where you live. Four things to match, in order of how much they matter.

1. The weight number. Non-negotiable. Substituting a category 3 for a category 4 will change the finished size of everything.

2. The total yardage, not the number of balls. This is where people get caught. A pattern calling for “3 skeins” means nothing on its own, because skein sizes differ enormously between brands — one brand’s 7 oz skein can hold more than double another’s 3.5 oz. Find the total yards or meters the pattern needs, then divide by the yardage of the yarn you are buying. Add ten percent, and buy it all at once so the dye lots match.

3. The fiber. Same thickness does not mean same behavior. Acrylic is springy, cheap, machine washable, and holds its shape — ideal for blankets, kids’ items, and amigurumi. Cotton is inelastic, heavy, and has no memory, so a cotton hat will stretch out and stay stretched; it is excellent for dishcloths, bags, and summer tops. Wool is warm, elastic, and blocks beautifully, but most of it needs hand washing. Substituting cotton for acrylic in a garment is technically possible and usually disappointing.

4. The gauge. Always swatch after substituting. Two yarns in the same category can still work up a stitch or two different over 4 inches.

When to ignore the hook on the label

The label’s hook suggestion aims for a balanced, general-purpose fabric. Two common projects want something else on purpose.

Amigurumi wants a smaller hook. Toys need a dense fabric so stuffing does not show through the gaps. With worsted yarn, go down to a 3.5 mm or 4 mm rather than the suggested 5.5 mm. Your hands will notice, and the toy will look properly made instead of saggy.

Blankets and shawls want a larger hook. Worked at the label’s gauge, a blanket often comes out stiff and board-like. One size up gives you drape.

How much yarn a project needs

Rough figures in category 4 worsted, for planning rather than for ordering:

Stitch choice moves these numbers more than people expect. Dense single crochet can use half again as much yarn as an open double crochet mesh over the same area, and textured stitches — bobbles, puffs, popcorns — are the hungriest of all. When in doubt, buy one extra ball. Returning it is easier than matching a dye lot three weeks later.

Frequently asked

What does “4-ply” or “8-ply” mean? It is the Australian and New Zealand system, and it refers to thickness rather than the literal number of strands twisted together. 4-ply is roughly fingering, 8-ply is roughly DK, 10-ply is roughly worsted.

Why is my hat too big when I followed the pattern exactly? Almost always gauge rather than yarn. Your tension is looser than the designer’s, so go down a hook size. Gauge is covered here.

Can I hold two thin yarns together to make a thicker one? Yes, and it works well. Two strands of DK held together behave roughly like a chunky. Swatch it, because the result is never exactly what arithmetic suggests.

Is expensive yarn worth it? For a blanket that will be dragged around by a toddler, no — acrylic is genuinely the right answer. For a garment you will wear for a decade, the fiber is most of what you are paying for and you will feel the difference every time you put it on.