🧶 Knitting & Crochet Yarn Studio

The four sums every knitter and crocheter does on the back of a pattern envelope: how many stitches to cast on at your gauge, how much yarn to buy, whether that leftover ball is enough, and which hook or needle a yarn actually wants. Nothing here is fetched from anywhere — the whole studio is arithmetic in your browser.

Your gauge (from a washed swatch, not a hopeful guess)

Stitches counted

Over (cm)

Rows counted

Over (cm)

Swatch weight (g, optional)

Cast on, and translate a pattern to your gauge

Finished width (cm)

Finished length (cm)

Pattern repeat (0 = any number)

Pattern says cast on (optional)

…at designer’s sts / 10 cm

Estimates, not a guarantee. Dye lots, tension drift, blocking and how tightly you wind all move the real number — buy one ball more than the sum says, and check the dye lot matches. A swatch you washed and dried is worth ten calculators.