Knitting Gauge Adjustment Calculator

Gauge is the number of stitches and rows you get per 4 inches (or per 10 cm) with a specific yarn and needle on a specific person.
It is not a fixed property of the yarn; it is a property of your hands.

When your gauge does not match the pattern, the finished item will come out the wrong size unless you correct the stitch count.
This calculator does that math automatically.

The formula is straightforward:

adjusted_cast_on = original_cast_on × (your_gauge ÷ pattern_gauge)

Example: a pattern calls for 80 stitches and uses a gauge of 20 stitches per 4 inches.
You swatch and get 18 stitches per 4 inches (your stitches are slightly larger).
Adjusted cast-on = 80 × (18 ÷ 20) = 72 stitches.

This works because each of your stitches is 4/18 inches wide instead of 4/20 inches wide.
To cover the same total width, you need fewer of your wider stitches.

For row gauge, the same principle applies in the vertical direction.
If the pattern says knit 100 rows and you have 26 rows per 4 inches instead of the pattern’s 28, you need: 100 × (26 ÷ 28) = 93 rows to reach the same finished height.

One practical note: try adjusting needle size before adjusting stitch count.
Going up or down half a needle size (e.g., US 7 to US 8) often brings your gauge to match the pattern without any math.
Swatching after washing and blocking is also essential — many yarns tighten or relax significantly after their first wet.

When stitch adjustment is unavoidable — for example, you are knitting with a different yarn and cannot reach the pattern gauge — this calculator gives you the corrected numbers.
Round to the nearest even number if the pattern uses a stitch pattern that requires an even or multiple count (ribbing, cables, etc.).