Guides · knitting math, shown in full
A custom-fit sweater pattern from your own gauge
You do not need a pattern that happens to match your gauge. You need your gauge — and a pattern derived from it. Every count below comes out of your swatch and your tape measure; the arithmetic is mechanical, which is exactly why software should do it.
Start from the swatch, not the pattern
Knit a generous swatch (at least 6 in square), wash and block it as you will the sweater, and measure over 4 in. The example below is a fine-gauge tee measured at 28 sts and 38 rows per 4 in — that is 7 sts and 9.5 rows per inch.
Everything else is derivation
- Width: a 36 in finished chest ÷ 2 × 7 sts/in, plus 2 seam sts, rounded to the 1x1 rib → cast on 128 sts per piece.
- Length: 22 in of body × 9.5 rows/in → 208 rows, hem included.
- Sleeve taper: from a 48-st cuff to 112 sts at the upper arm — 32 paired increases, spaced evenly over the sleeve so the last one lands below the underarm (inc 1 st at each end of every 6th row 6 times; then inc 1 st at each end of every 4th row 26 times).
Row gauge is not optional
Stitch gauge sets the width; row gauge sets everything vertical — body length, armhole depth, and where a colour motif sits. A swatch that lies by half a row per inch makes this 208-row body come out about 1.25 in too long, and drags the motif with it. Measure rows as carefully as stitches.
Change any input — chest, length, gauge — and every downstream count shifts: that is why re-deriving beats adapting. Our engine recomputes the whole pattern and then audits it: shoulders + neck must equal the cast-on, the chart must fit between the seams, every partition is re-checked before a single row is printed.
Draft a pattern from your gauge →It opens live and editable — change any number and the whole pattern re-derives.