Guides · knitting math, shown in full
Intarsia chart placement math
Placing an intarsia motif is two small allocation problems — one horizontal, one vertical — plus a parity rule that, if you miss it, knits your motif mirror-imaged. Here is the math, worked on a real front.
Horizontal: split what the seams leave
The front is 100 sts wide, but the outermost 1 st on each edge disappears into the mattress seam. Never let the chart touch it, or the seam eats your motif’s edge columns.
- Available field: 100 − 2 = 98 sts
- Chart width: 25 sts → spare = 73 sts
- Centred: 73 ÷ 2 → 37 sts of background before the chart, 38 after (the odd stitch goes to one side — pick one and keep it; nobody can see half a stitch of asymmetry, but a wandering chart is visible).
- Check: 37 + 25 + 38 = 100 sts. It must equal the cast-on exactly.
Vertical: centre it in the plain region
The motif must fit between the top of the hem and the first neck-shaping row — not the whole body:
- Neck shaping starts at row 126 of 144 — the front scoop takes the last 18 rows.
- Plain region: 126 − 16 hem rows = 110 rows; the chart is 21 rows tall.
- Centred: (110 − 21) ÷ 2 → 44 plain rows above the hem, 45 below the neck.
The parity rule
Chart row 1 must land on a right-side row, because RS rows are read right-to-left and WS rows left-to-right. Here row 1 falls on body row 16 + 44 + 1 = 61 — odd, so a RS row. If your own arithmetic puts it on an even row, shift the motif one row: an asymmetric motif started on a WS row knits up flipped left-to-right, and you will not see it until several evenings too late.
Let the engine place your chart →It opens live and editable — change any number and the whole pattern re-derives.