The yarn you pick for an amigurumi affects everything: the size of the finished plushie, the visibility of the stitches, how stuffing-firm the fabric feels, whether the eyes look right, and how much the surface fuzz hides imperfections.

This guide walks through what to look for, what to skip, and which yarn weight + hook pairing gives you the most predictable result for an amigurumi.

TL;DR

For most amigurumi: worsted-weight (weight 4) cotton or acrylic with a 3.5–4 mm hook.
For tiny detail work: DK (weight 3) cotton with a 2.5–3 mm hook.
For chunky display pieces: bulky (weight 5) acrylic with a 5 mm hook.
Skip: anything fuzzy, anything with long fibers, anything single-ply.

What makes a yarn good for amigurumi?

Three things. In order of importance:

1. Tight gauge (no peeking stuffing)

The whole point of amigurumi is that it's stuffed. If your stitches are loose, the stuffing pokes through and the surface looks lumpy. The fix isn't to stuff less, it's to use a hook half a size smaller than the yarn label suggests to get a tight, dense fabric.

Worsted-weight yarn typically calls for a 5–5.5 mm hook on the label. For amigurumi, drop to 3.5–4 mm.

2. Smooth surface (so the eyes show up)

The eyes, whether safety eyes or embroidered, are the personality of the piece. They need to sit on a smooth, flat surface to read correctly. Fuzzy yarns hide the eyes, scratch the lens of safety eyes, and make the embroidery wander.

Use: mercerized cotton, brushed acrylic, smooth wool blends. Skip: mohair, alpaca-blend, eyelash yarn, anything that says "halo" or "fluffy" on the label.

3. Stitch definition (so you can see your work)

Amigurumi is built one stitch at a time, often into the back loop only or with subtle increases. You need to be able to see each stitch clearly, both for your own sake while crocheting and so the finished piece has texture, not a blur.

Cotton has the best stitch definition. Acrylic is a close second. Wool depends on the brand (worsted-weight wool with a tight twist is fine; soft single-ply wool is too fuzzy).

Cotton vs. acrylic vs. wool: which is best?

The honest answer: it depends on what the amigurumi is for.

Cotton

Pros: Best stitch definition. Doesn't pill. Holds shape well, perfect for amigurumi that need to stand up. Washes well (machine washable on cold). Affordable.

Cons: Less stretch, can be tough on the hands during long sessions. Slightly heavier than acrylic, which matters for hanging amigurumi (mobiles, etc.). Color selection varies by brand.

Best for: baby amigurumi (washable), display pieces (holds shape), realistic animals (stitch definition).

Recommended brands: Lily Sugar 'n Cream, Yarnspirations Lily, Drops Paris, Hobbii Friends Cotton 8/4.

Acrylic

Pros: Cheapest. Massive color selection. Lightweight. Very stretchy (forgiving on the hands). Holds dye well, good for vivid colors.

Cons: Pills over time. Stitches less defined than cotton. Some brands feel plasticky.

Best for: kid amigurumi (cheap to replace if lost), large statement pieces, bright/neon colors.

Recommended brands: Red Heart Super Saver, Yarn Bee Soft Secret, Brava Worsted (KnitPicks), Caron Simply Soft.

Wool

Pros: Beautiful natural feel. Felts to itself a bit (which actually helps amigurumi look polished). Holds shape. Eco-friendly.

Cons: Hand-wash only (or wool-cycle machine wash with care). More expensive. Some kids/pets/owners are sensitive to it. Can shed.

Best for: heirloom amigurumi, gifts for adult collectors, neutral-tone display pieces.

Recommended brands: Cascade 220 (worsted), Wool of the Andes (KnitPicks), Drops Lima.

Yarn weight + hook pairing chart

Yarn weight	Hook size (amigurumi)	Finished size (6-sc magic ring → ~20 rows)	Best for
Lace (0)	2.0 mm	~2 inches	Miniatures, doll accessories
Sport (2)	2.75 mm	~3 inches	Small detailed pieces, keychain plushies
DK (3)	3.0 mm	~3.5 inches	Detailed amigurumi, baby toys
Worsted (4)	3.5–4.0 mm	~4.5 inches	Standard amigurumi (the default)
Bulky (5)	5.0 mm	~6 inches	Large display pieces, fast finishes
Super bulky (6)	6.5 mm	~8+ inches	Statement amigurumi, jumbo plushies

The key takeaway: drop the hook size by half a size to a full size from what the yarn label recommends. The yarn label is for garments where you want drape, you want the opposite for amigurumi.

What to skip

Eyelash / fun fur yarn, impossible to count stitches, looks like a blob.
Mohair, alpaca, single-ply wool, too fuzzy, hides stitch definition, scratchy.
Boucle yarn, texture is unpredictable, stitch counts get wonky.
Velvet / chenille yarn (Bernat Blanket Yarn type), beautiful but worming/twisting issues, hides stitch detail. Only use if you specifically want a fluffy plushie texture and you're okay with worming.
Variegated yarn with long color repeats, pools weirdly on small amigurumi pieces. Short-repeat variegated is fine.

Stuffing matters too

A great yarn with bad stuffing still looks bad. Use polyester fiberfill (the white pillow stuffing kind), not cotton balls or rags. Stuff firmly, amigurumi should feel solid when squeezed, not squishy. Add stuffing in small handfuls and use the back end of your hook to push it into the limbs and head.

For weighted amigurumi (so they sit upright), add a small bag of poly pellets or rice in the bottom before stuffing.

Generate amigurumi patterns sized to your yarn

CrochetAI lets you specify the yarn weight when you describe an amigurumi, say "worsted-weight cotton" or "DK acrylic" and the pattern adjusts gauge, stitch counts, and the final size accordingly. No converting from a pattern written in a yarn you don't have.

Try CrochetAI free, or browse amigurumi patterns to see how the AI sizes patterns to the yarn you tell it about.

Ready to cast on? Try the free purple octopus amigurumi pattern, written for worsted-weight yarn and a 3.5 mm hook.