Curtain Panel Calculator
Calculate curtain panel easily with our free tool. Get practical results, tips, and comparisons for everyday decisions.
Reviewed by Daniel Agrici, Founder & Lead Developer
Formula
Total Fabric = (Cut Length x Total Fabric Widths) / 36 yards
Where Cut Length = Window Height + Rod Height + Hem Allowance + Header Allowance, and Total Fabric Widths = (Window Width x Fullness Multiplier / Fabric Bolt Width) x Number of Panels. The result in inches is divided by 36 to convert to yards.
Worked Examples
Example 1: Standard Living Room Curtains
Problem:Window is 72 inches wide and 84 inches tall. Using 2x fullness, 2 panels, 54-inch fabric, 8-inch hem, 4-inch header, rod mounted 4 inches above frame.
Solution:Total width needed: 72 x 2 = 144 inches\nWidth per panel: 144 / 2 = 72 inches\nFabric widths per panel: ceil(72 / 54) = 2\nTotal fabric widths: 2 x 2 = 4\nCut length: 84 + 4 + 8 + 4 = 100 inches\nTotal fabric: 100 x 4 = 400 inches = 11.11 yards
Result:4 fabric widths needed | Cut length: 100 in | Total: 11.11 yards
Example 2: Sheer Bedroom Curtains
Problem:Window is 48 inches wide and 96 inches tall. Using 2.5x fullness, 2 panels, 54-inch sheer fabric, 6-inch hem, 3-inch header, rod 6 inches above.
Solution:Total width needed: 48 x 2.5 = 120 inches\nWidth per panel: 120 / 2 = 60 inches\nFabric widths per panel: ceil(60 / 54) = 2\nTotal fabric widths: 2 x 2 = 4\nCut length: 96 + 6 + 6 + 3 = 111 inches\nTotal fabric: 111 x 4 = 444 inches = 12.33 yards
Result:4 fabric widths | Cut length: 111 in | Total: 12.33 yards
Frequently Asked Questions
What is curtain fullness and what multiplier should I use?
Curtain fullness refers to the ratio of fabric width to the actual window width, which creates the gathered, flowing appearance of properly hung curtains. A fullness multiplier of 1.5x means you use 1.5 times the window width in fabric, creating a minimal gather suitable for modern, streamlined looks. A 2x multiplier is the standard recommendation for most curtain styles, providing a classic, well-draped appearance with moderate gathers. A 2.5x to 3x multiplier creates luxurious, deeply gathered curtains typical of formal rooms and heavyweight fabrics. Sheer curtains often require 2.5x to 3x fullness because the fabric is thin and needs more gathering to provide adequate coverage and visual appeal.
How do I measure my window correctly for curtain panels?
Proper measurement is the foundation of well-fitting curtains. For width, measure the window frame from left to right, then add 4 to 8 inches on each side so the curtains extend beyond the frame and block light leakage. For height, measure from where the curtain rod will be mounted to where you want the curtains to end. Standard options include sill length (ending at the window sill), below sill (4 inches below), and floor length (ending half an inch above the floor). For a dramatic look, puddle-length curtains extend 2 to 6 inches onto the floor. Always measure from the rod position, not the top of the window frame, and mount the rod 4 to 6 inches above the frame for a taller appearance.
References
Reviewed by Daniel Agrici, Founder & Lead Developer · Editorial policy