Knitting Pattern Resizer
Work out how many stitches to cast on to hit an exact finished measurement — for resizing a pattern to fit you, not just matching the designer's original size.
Don't forget ease
"Target finished measurement" should already include the ease you want — if you want a sweater to fit with 2 inches of positive ease over your 36in chest, enter 38, not 36. This tool gives you the cast-on count for one flat measurement; for a full garment with waist shaping, sleeve tapering, etc., repeat the calculation at each key measurement point.
Cast-on numbers need more than a stitch repeat
A k2p2 rib needs a cast-on that's a multiple of 4 to repeat cleanly, but most patterns also add a couple of extra stitches on each side so the ribbing looks balanced and symmetrical at both edges, or to allow for a seam allowance on a piece that will be sewn together. If your pattern has a stated formula like "multiple of 4, plus 2," enter 4 in the repeat field and add those extra 2 stitches to the result yourself — this tool rounds to a clean repeat but doesn't know about pattern-specific edge-stitch additions.
Knit ease runs a bit different from crochet ease
Because stockinette and ribbed fabric stretch more than most crochet fabric, a knit sweater can often use slightly less positive ease than a crochet sweater and still feel comfortable — a fitted knit cardigan might use 1 inch of ease where an equivalent crochet piece wants 2. If you're converting a crochet pattern's fit preferences to knitting, or vice versa, don't assume the same ease numbers carry over directly.
For a full garment, swatch in the actual stitch pattern for each section rather than assuming one plain-stockinette gauge applies everywhere — a cabled panel in particular pulls in narrower than the stockinette around it, sometimes significantly, and needs its own gauge check before you resize that section.