Knitting calculator for even increases, decreases and cast-on
Two jobs come up in almost every knitting project: spreading a number of increases or decreases evenly across a row or round, and working out how many stitches to cast on for a given width. This knitting calculator does both. Enter the stitches you have and how many to add or remove, and it writes out the pattern; or enter a gauge swatch and your target size.
It works for flat rows and for rounds, uses plain arithmetic, and runs in your browser. Nothing is uploaded.
How to use the Knitting Increase/Decrease Calculator
- For changes, choose Increase or Decrease, enter the stitches on the needle and how many to add or remove.
- Read the pattern, for example “(K10, inc 1) × 8”, and work it across the row or round.
- For a cast-on, switch to Cast on from gauge and enter the stitches and rows in your swatch and its measurements.
- Enter the width and length you want and any stitch multiple, such as a multiple of 4 plus 2 edge stitches.
- Copy the result into your notes.
Knitting Increase/Decrease Calculator features
Even spread
Segments differ by at most one stitch, with the shorter and longer runs spread through the row.
Compact pattern
Repeating sections are shown as “(K4, inc 1) × 6” instead of a long list.
Gauge to cast-on
Stitches and rows from your swatch, rounded to your stitch pattern.
Limits checked
Decreases are limited to half the stitches because each k2tog uses two; increases to the number of stitches.
How the spread works
With S stitches and N increases, the row is divided into N segments that together hold the S stitches. After each segment you work an increase. The segments are as equal as possible: some hold q stitches and some q + 1, where q is S ÷ N rounded down. The tool places the longer segments evenly rather than all at the end.
For decreases each k2tog uses two stitches, so the plain knit stitches are S − 2N, shared among N segments. For example, 80 stitches decreasing 8 leaves 64 plain stitches in 8 segments of 8, so you work K8, k2tog eight times and end with 72. The mathematics is arithmetic, so no source is needed; the stitch names are standard knitting abbreviations.
| Start | Change | Pattern | End |
|---|---|---|---|
| 80 | +8 | (K10, inc 1) × 8 | 88 |
| 80 | −8 | (K8, k2tog) × 8 | 72 |
| 30 | −10 | (K1, k2tog) × 10 | 20 |
| 50 | +12 | 10 segments of 4 and 2 of 5 | 62 |
Casting on from gauge
Gauge is the number of stitches and rows in a measured piece of fabric. Divide the swatch stitches by the swatch width to get stitches per centimetre or inch, multiply by the width you want, then round to the nearest number that fits your stitch pattern (a multiple of m plus p). Rows work the same way from the swatch height. Knit the swatch in the stitch pattern you plan to use and wash and block it first, since many yarns relax or shrink. The calculator also shows the width you will actually get after rounding. For yarn quantities, use the yarn calculator.
Tips
In a round, start the pattern at the beginning-of-round marker. For a long row you can mark each repeat. If you need uneven shaping, such as a raglan, work this calculation for each section separately. To keep count while you knit try the tally counter.
Knitting Increase/Decrease Calculator FAQ
How do I evenly space increases in knitting?
Divide the stitches by the number of increases. If it does not divide exactly, some runs are one stitch longer. The calculator lists the runs for you.
How do I evenly decrease stitches?
Each k2tog uses two stitches, so subtract twice the number of decreases from your stitches and share the rest among the decreases. Enter both numbers and read the pattern.
Why can I not decrease more than half my stitches?
Every decrease uses two stitches, so spreading more than half your stitches in decreases would leave no plain stitches between them.
How do I work out a cast-on from gauge?
Divide the swatch stitches by the swatch width, multiply by the finished width, and round to fit your stitch pattern.
Does it work for knitting in the round?
Yes. Treat the round as one long row and place a marker at the start.
Which increase should I use?
Any. The calculator only tells you where to place them; M1L, M1R, kfb and yarn overs all work, depending on the look you want.