Knitting Gauge Calculator – Swatch to Stitches Per Inch

Count stitches and rows across the middle of your washed swatch and enter them here. You get your gauge per inch, per 4 inches, and per 10 cm, and when you add the pattern’s gauge, exactly what your tension does to the finished size. Reworking a pattern at a different gauge is a job for the gauge converter in the related list.

Your Swatch

Stitches counted

Rows counted

Counted over inches

Compare against my pattern’s gauge

Your Gauge

4.5stitches per inch

6 rows per inch · 18 sts per 4 in

Per 4 inches18 sts · 24 rows
Per 10 cm17.7 sts · 23.6 rows

The Formula

stitches per inch = stitches counted ÷ inches measured · rows per inch = rows counted ÷ inches measured

Count over 4 inches, not 1: edge stitches knit uneven, and a wide count averages them out. Half stitches are real readings: keep them.

What a Gauge Miss Costs

finished width = pattern’s stitch count ÷ your stitches per inch

The pattern’s stitch count is fixed; your tension decides what width those stitches make. One stitch per 4 inches off, on a 200-stitch sweater, moves the chest by about 2 inches.

Worked Example

Your washed swatch counts 18 stitches and 24 rows over 4 inches; the pattern asks for 20 over 4 at a 40 in finished chest:

Your gauge: 18 ÷ 4 = 4.5 stitches per inch, 6 rows per inch.
The pattern’s chest is 40 × (20 ÷ 4) = 200 stitches. At your 4.5: 200 ÷ 4.5 = 44.4 in: nearly four and a half inches oversized.
The fix: go down a needle size or two and swatch again, or follow the sizes-down numbers the comparison suggests.

Standard Gauge by Yarn Weight

The Craft Yarn Council’s stockinette ranges, the starting point before your own swatch.

Weight	Stitches per 4 in	Needles (US)	Needles (mm)
1 · Super fine	27–32	1–3	2.25–3.25
2 · Fine (sport)	23–26	3–5	3.25–3.75
3 · Light (DK)	21–24	5–7	3.75–4.5
4 · Medium (worsted)	16–20	7–9	4.5–5.5
5 · Bulky	12–15	9–11	5.5–8
6 · Super bulky	7–11	11–17	8–12.75
7 · Jumbo	6 or fewer	17+	12.75+

How to Swatch So the Number Is True

Cast on 6 inches’ worth and knit 6 inches, in the pattern stitch. Rib, garter, lace, and stockinette each gauge differently.
Wash and dry it like the garment will live. Superwash wool grows; cotton relaxes. An unwashed swatch promises a size the first wash takes back.
Measure the middle with a rigid ruler, pins at each end of the 4 inches, and count between the pins: twice.
In the round? Swatch in the round. Most people purl at a different tension than they knit, and flat swatches hide it.

Assumptions and Defaults

Per-10 cm figures use 1 in = 2.54 cm exactly.
The comparison assumes the pattern’s stitch count scales with its stated gauge and width: true for plain pieces, approximate around shaping.
Row gauge is optional; width math needs only stitches.

Gauge Questions, Answered

How do I calculate knitting gauge?

To calculate knitting gauge, divide the stitches you counted by the inches you measured, so 18 stitches over 4 in is 4.5 stitches per inch, and count rows the same way. The calculator takes your raw counts directly, so you don’t need to do the division in your head at the yarn store.

Does knitting gauge really matter for a scarf?

For a scarf’s width, gauge matters only a little, since a scarf an inch wider than planned is still a scarf. It matters a great deal for yarn, though, because off-gauge fabric changes how many yards the scarf uses, and for anything fitted, gauge is the difference between a sweater and a tent.

What if my stitch gauge matches but my row gauge doesn’t?

If your stitch gauge matches but your row gauge doesn’t, keep knitting, and work lengths to measured inches instead of row counts wherever the pattern gives lengths. Recount rows only where shaping is spaced by rows, such as raglans, sleeve tapers, and crowns, because stitch gauge is the one worth swatching again for.

How do I change my knitting gauge?

To change your knitting gauge, try a different needle size first, since one US size moves stockinette by roughly half a stitch per 4 in. Needle material comes second, because slick metal loosens most knitters and grippy wood tightens them, and a different yarn comes last; deliberately knitting tighter rarely holds steady for a whole sweater.

Why measure a knitting swatch after washing?

You measure a swatch after washing because fabric relaxes in water: stitches bloom, superwash yarn stretches, and cotton drops in length. The washed measurement is the one your finished garment will show, and comparing before and after once is usually enough to convince anyone never to skip the wash.

Gauge ranges: Craft Yarn Council yarn weight standards.