Gauge formulas
Stitches per inch (or cm) = stitches counted ÷ width measured
Cast-on = finished width × stitches per inch, rounded to the stitch repeat
Resized count = pattern stitches × your gauge ÷ pattern gauge
Cast-on = finished width × stitches per inch, rounded to the stitch repeat
Resized count = pattern stitches × your gauge ÷ pattern gauge
Patterns usually give gauge over 4 inches (10 cm). Twenty stitches over 4 inches is 5 stitches per inch, so a 40-inch-wide piece needs 200 stitches. If the stitch pattern works over a multiple — say a multiple of 4 plus 2 — the calculator rounds to the nearest count that fits.
Craft Yarn Council standard yarn weights
| # | Weight | Also called | Knit gauge (sts per 4 in) | Needles | Crochet gauge (sc per 4 in) | Hook |
|---|---|---|---|---|---|---|
| 0 | Lace | fingering 10-count crochet thread | 33–40 | 1.5–2.25 mm (US 000–1) | 32–42 dc | steel 1.4–1.6 mm / 2.25 mm |
| 1 | Super Fine | sock, fingering, baby | 27–32 | 2.25–3.25 mm (US 1–3) | 21–32 | 2.25–3.5 mm |
| 2 | Fine | sport, baby | 23–26 | 3.25–3.75 mm (US 3–5) | 16–20 | 3.5–4.5 mm |
| 3 | Light | DK, light worsted | 21–24 | 3.75–4.5 mm (US 5–7) | 12–17 | 4.5–5.5 mm |
| 4 | Medium | worsted, afghan, aran | 16–20 | 4.5–5.5 mm (US 7–9) | 11–14 | 5.5–6.5 mm |
| 5 | Bulky | chunky, craft, rug | 12–15 | 5.5–8 mm (US 9–11) | 8–11 | 6.5–9 mm |
| 6 | Super Bulky | super chunky, roving | 7–11 | 8–12.75 mm (US 11–17) | 7–9 | 9–15 mm |
| 7 | Jumbo | jumbo, roving | 6 or fewer | 12.75 and up mm (US 17 and up) | 6 or fewer | 15 mm and up |
From the Craft Yarn Council Standard Yarn Weight System. These are typical ranges for stockinette and single crochet; your own gauge can sit outside them.
How to measure a swatch properly
- Make it big — at least 6 × 6 in (15 × 15 cm) — in the stitch pattern the project uses.
- Wash and block it the way you will treat the finished piece. Many yarns grow or shrink.
- Measure in the middle, away from the edges, over 4 in (10 cm). Count half stitches too.
- Too many stitches? Your fabric is tighter than the pattern — go up a needle or hook size. Too few? Go down.
Planning a blanket or scarf? Once you have a swatch, the yarn calculator estimates how much yarn you need from its weight.
Last reviewed: 2026-10-04 · Disclaimer