Hook a swatch, block it, count across the middle 4 inches, and enter the counts. You get your gauge per inch and per 10 cm, the stitches any width needs, and what your tension does to the pattern’s finished size.
Your Swatch
Your Gauge
3stitches per inch
3.5 rows per inch · 12 sts per 4 in
- Per 4 inches12 sts · 14 rows
- Per 10 cm11.8 sts · 13.8 rows
- Stitches for 20 in60
- Stitches for 40 in120
The Formula
stitches per inch = stitches counted ÷ inches measured · rows per inch = rows counted ÷ inches measuredCount whole and half stitches across the middle 4 inches, away from the edges and the foundation chain.
Worked Example
Your blocked dc swatch counts 12 stitches and 14 rows over 4 inches; the pattern wants 14 over 4 at a 40 in width:
- Your gauge: 12 ÷ 4 = 3 stitches per inch, 3.5 rows per inch.
- The pattern’s width is 40 × 3.5 = 140 stitches. At your 3 per inch: 140 ÷ 3 = 46.7 in: nearly seven inches oversized.
- The fix: a smaller hook and a fresh swatch. One hook size moves most crocheters about half a stitch per 4 inches.
Crochet Gauge by Yarn Weight
The Craft Yarn Council’s single crochet ranges: starting points until your swatch speaks.
| Weight | Sc per 4 in | Usual hooks |
|---|---|---|
| 1 · Super fine | 21–32 | B-1 to E-4 (2.25–3.5 mm) |
| 2 · Fine (sport) | 16–20 | E-4 to 7 (3.5–4.5 mm) |
| 3 · Light (DK) | 12–17 | 7 to I-9 (4.5–5.5 mm) |
| 4 · Medium (worsted) | 11–14 | I-9 to K-10½ (5.5–6.5 mm) |
| 5 · Bulky | 8–11 | K-10½ to M-13 (6.5–9 mm) |
| 6 · Super bulky | 7–9 | M-13 to Q (9–15 mm) |
| 7 · Jumbo | 6 or fewer | Q and up (15 mm +) |
How to Swatch So the Number Is True
- Swatch in the project stitch: dc runs taller and wider than sc at the same hook; granny clusters gauge differently again.
- Make it 6 inches and measure the middle 4: foundation chains pull in, top edges flare.
- Block or wash it first the way the finished piece will live, especially cotton and acrylic that relax with heat.
- Count post by post: in dc fabric, each vertical post is one stitch; count the spaces in filet-style fabric.
Assumptions and Defaults
- Per-10 cm figures use 1 in = 2.54 cm exactly.
- The pattern comparison scales stitch count by stated gauge and width: exact for plain rectangles, approximate around shaping.
Gauge Questions, Answered
How do I measure crochet gauge?
To measure crochet gauge, make a swatch larger than 4 in in your project stitch, block it, and count the stitches and rows across the middle 4 in. Dividing by 4 gives the per-inch figures, although the calculator takes your raw counts directly.
Does hook size or tension matter more for crochet gauge?
Tension matters more than hook size, since two crocheters using the same hook and yarn can differ by two stitches per 4 in. The hook is the adjustment you control: go up a size to loosen the fabric and down a size to tighten it, which is why half sizes exist.
Why does my blanket gauge drift as I go?
Blanket gauge drifts because most crocheters relax after the first evening of work. Measure 4 in at the start, the middle, and the current edge of a long project, since a drift of half a stitch per 4 in widens a blanket by two inches, and check again whenever you return to a project after weeks away.
Do turning chains count as a stitch?
In single crochet, turning chains do not count as a stitch, whereas in double crochet your pattern decides, and many count the ch-3 as the first dc. For gauge it rarely matters, since you count stitches across the middle of the swatch, away from the edges where that convention shows.
Gauge and hook ranges: Craft Yarn Council yarn weight standards.