Sleeve Decrease Spacing Calculator

Sleeve shaping is the most common place where home knitters get stuck. The pattern says “decrease evenly,” and you have to work out what that means in concrete row terms. This calculator does the arithmetic.

The setup: a sleeve narrows from upper-arm width down to wrist width over some number of rows. Each decrease row removes 2 stitches (one at each side of the sleeve via k2tog and ssk). So:

decrease rounds needed = (start stitches − end stitches) ÷ 2

For 64 → 40 stitches: (64 − 40) ÷ 2 = 12 decrease rounds.

Spacing them evenly across the sleeve length:

interval = total rows ÷ decrease rounds

For 90 rows ÷ 12 = 7.5 rows. Since you can’t decrease at row 7.5, the practical solution is to use a mix of 7-row and 8-row intervals.

Worked example: 12 decrease rounds, 90 total rows, interval 7.5.

• 6 intervals of 8 rows = 48 rows
• 6 intervals of 7 rows = 42 rows
• Total = 90 rows. ✓

Alternative: alternate strictly (8, 7, 8, 7, …) — this gives the smoothest visual taper because the intervals interleave. Pick whichever feels easier to track.

For very gentle shaping (long sleeve, small decrease), the interval may be 12+ rows. Looks elegant but is hard to remember without a row counter. Many knitters mark every Xth row with a removable stitch marker on the row above to know when to decrease.

For aggressive shaping (cuff much narrower than upper-arm), the interval may be 2-4 rows. Easy to remember but creates a visible diagonal line of decreases. Some patterns deliberately use this for a fitted sleeve cap or a fitted cardigan body that wants to show shaping.

Common shaping notation in patterns:

“Decrease 1 stitch each side every 8 rows 6 times, then every 6 rows 4 times” means: 6 decrease rounds spaced 8 rows apart, then 4 decrease rounds spaced 6 rows apart, for a total of 10 decrease rounds and 72 rows of shaping.

Where to place the decreases: just inside the seam edges, typically 2-3 stitches from the edge. SSK at the right (shaping the stitches that lean to the right), K2tog at the left (leaning the other way) gives a clean mirror-image taper. For magic-loop sleeves worked in the round, the decreases happen at the underarm marker.

This calculator handles symmetric edge decreases. Patterns with unusual shaping (front darts, asymmetric cardigans) need the decreases planned by hand against a specific schematic.