Tool 02 · Window planning
Curtain fabric calculator
Plan curtain fabric with fullness, panel count, hems, joined drops, pattern repeat, and waste included in the estimate.
Your result will appear here
Clear working, useful estimate.
Enter your project details and select Calculate estimate. We only show a result after valid measurements are submitted.
Planning estimates vary with fabric, print, shrinkage, cutting technique, and project details.
How the estimate works
From track width to fabric length
Fullness multiplies the track or pole width to estimate the total finished curtain width. That width is divided across the panels. The side-hem input is per side of each panel, so it is added twice to each panel's cut width. The calculator finds the smallest equal number of full-width drops per panel that can cover it. Each join consumes one allowance from both joined edges, reducing joined usable width by twice the entered seam allowance; it is not added again to the drop length.
With the example defaults, a 200 cm track at 2× fullness needs 400 cm of finished width, or 200 cm per panel. Adding 10 cm side hems on each side gives 220 cm cut width. A 140 cm roll has 136 cm usable width; two drops joined with a 2 cm allowance yield 268 cm. Four total drops at 260 cm each use 1,040 cm before 10% waste, or 11.44 m recommended.
total finished width = track width × fullness ratiojoined width = drops × usable width − (drops − 1) × 2 × joining seamrecommended length = total drops × cut length per drop × (1 + waste%)Common questions
Curtain planning notes
What does fullness mean?
Fullness is the ratio between the fabric width and the track or pole width. A ratio of 2 means the flat fabric width is twice the track width before gathering or pleating.
Why might a panel need more than one drop?
If the cut width for a panel is wider than the usable roll width, multiple full-width lengths can be joined. Each join reduces the combined usable width by the two seam allowances specified in the calculation rules.
Does the estimate include lining or matching across panels?
No. Add lining, interlining, borders, and other components separately. Pattern repeat is applied to each drop along the roll; horizontal matching is not calculated.