How it works
Gap & finished width
Available fabric, pleat count, and pleat depth are the inputs. The gap uses all remaining fabric:
G = (F − n × 2 × depth) ÷ (n − 1)
The finished width is the sum of all gaps — no fabric is left over:
W = (n − 1) × G = F − n × 2 × depth
Changing any of the three fixed inputs (fabric, width, depth) auto-updates the pleat count.
Fabric used
All available fabric is accounted for:
F = n × 2 × depth + (n−1) × G
Every pleat folds 2×depth of flat fabric. The gaps lie flat and together span the finished width.
Example — 226 cm fabric, 17 pleats
F 226 cm available fabric
n 17 pleats
depth 2 cm (fixed)
G (226−68)÷16 = 9.875 cm
W 16 × 9.875 = 158 cm
Pleats 17 × 2×2 = 68 cm
Gaps 16 × 9.875 = 158 cm
Total 226 cm