Knitting Gauge Calculator for Cast-On Stitches
This calculator converts a knitted gauge swatch into the cast-on stitches and total rows for any finished size. Enter how many stitches and rows you counted over a measured width and height, then the width and height you want the piece to be. It works out your stitch and row gauge and multiplies through to whole-number counts, in inches or centimeters.
How to use a knitting gauge
- Knit and block a swatch, then choose the in or cm unit toggle at the top right.
- Enter Stitches in swatch and Swatch width for the horizontal count you measured.
- Enter Rows in swatch and Swatch height for the vertical count you measured.
- Enter the Target width and Target height of the finished piece.
- Read Cast-on stitches and Total rows in the result cards, along with your stitch and row gauge.
- Click Copy result to save the numbers for your pattern notes.
Examples
Worsted sweater front at 5 sts and 7 rows per inch
20 sts over 4 in, 28 rows over 4 in, target 18 x 24 in
90 cast-on stitches, 168 total rows
Fine scarf at 6 sts and 8 rows per inch
24 sts over 4 in, 32 rows over 4 in, target 8 x 60 in
48 cast-on stitches, 480 total rows
A gauge that is not a whole number per inch
21 sts over 4 in, 29 rows over 4 in, target 20 x 22 in
105 cast-on stitches, 160 total rows (5.25 sts and 7.25 rows per inch)
Frequently asked questions
How do I calculate cast-on stitches from gauge?
Divide the stitches in your swatch by its width to get stitches per inch, then multiply by the finished width you want and round to the nearest whole stitch. For example 20 stitches over 4 inches is 5 per inch, so an 18 inch width needs 90 stitches cast on.
Do I have to fill in the row fields?
The on-page tool keeps every field filled so it can show all four results at once, including row gauge and total rows. The underlying engine and API treat rows as optional: omit the row and height fields there and you get just stitches per inch and the cast-on count.
Can I work in centimeters instead of inches?
Yes. Use the in and cm toggle at the top right. Switching converts your measurements automatically and, in cm mode, quotes gauge per 10 cm the way most metric patterns do. The cast-on and total row counts stay the same for the same real-world size.
Why is matching gauge so important?
Gauge sets the finished size. If your stitches per inch differ from the pattern, the garment comes out larger or smaller, and a small per-inch difference multiplies across a wide piece into inches of error. Always swatch in the actual project yarn and needles, then block before measuring.
Should I measure over 4 inches or 1 inch?
Measure over 4 inches or more and let the tool divide. Counting across a larger span averages out small irregularities in tension, so the stitches-per-inch figure is far more accurate than a single-inch count, which is easily thrown off by one loose or tight stitch.
Does it account for pattern repeats or edge stitches?
No. It returns the raw stitch count for the width. Round that to your stitch-pattern multiple, then add any selvage, border or seam stitches your pattern calls for. For a repeat of 6, for instance, adjust 90 up to 90 or down as your design requires.
How does it round the counts?
Cast-on stitches and total rows are rounded to the nearest whole number, since you cannot knit a fraction of a stitch. Stitch and row gauge are shown to a few decimals so you can see the underlying figure, such as 5.25 stitches per inch.
What if my gauge does not fit the pattern's needle size?
Change needle size to fix gauge, not the pattern. Too many stitches per inch means your fabric is tight, so go up a needle size; too few means it is loose, so go down. Reswatch until the stitch gauge matches, since stitch gauge drives width most directly.
Is anything I enter sent to a server?
No. The math runs entirely in your browser, so your measurements stay on your device. The same pure engine also backs the optional API for anyone who wants to script gauge math.
Learn more
- How to knit an accurate gauge swatch
Swatch big, block it, and measure over four inches so your cast-on math is right the first time. A practical guide for knitters.
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