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Roman Blind Calculator — Fabric for Roman Blinds
Calculate fabric, lining, dowels, rings and cord for roman blinds.
Recommended for all roman blinds
How We Calculate This
Roman Blind Fabric Calculation
Cut Width = Blind Width + (Side Hem × 2)
Face Cut Drop = Blind Drop + Bottom Hem + Heading
Roman blinds hang flat (no fullness), so if the cut width is wider than your fabric roll the calculator joins extra widths — Widths Joined = round up (Cut Width ÷ Fabric Width) — and multiplies the metres accordingly.
Traditional rod pockets are made from the lining, not the face fabric, so the face is cut as a flat panel and the lining is cut longer than the face by the rod-pocket allowance (about 4–5 cm per rod). That is why the lining requirement can exceed the face-fabric requirement. The fold sizes follow the standard rule of equal full folds plus a half-depth bottom fold (Full Fold = Blind Drop ÷ (Folds − ½)).
Frequently Asked Questions
Most roman blinds have 3-8 folds depending on the drop. A good rule is one fold every 20-25 cm. Short blinds (100 cm) suit 3-4 folds. Tall blinds (200 cm+) look best with 6-8 folds.
Inside mount fits within the window recess for a clean look but requires precise measurements. Outside mount overlaps the window frame, covering more light gaps. Add 5 cm each side and 10-15 cm at the top for outside mount.
Lining is recommended for most roman blinds. It protects the face fabric from sun damage, improves the view from outside, adds body for neater folds, and helps block light. Use blackout lining for bedrooms.
Use 6mm or 8mm fibreglass rods or wooden dowels. They should be 2-3 cm shorter than the finished blind width. Fibreglass is preferable as it does not warp in humidity.
Each cord column needs the full drop length plus the width of the blind (to run across to the operating side) plus 30 cm for the cord tail. Multiply by the number of cord columns (usually 3).
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Last updated: February 2026
All calculations are estimates. Always verify quantities before cutting or purchasing fabric.