How to Calculate Drapery Yardage: Step-by-Step with Pattern Repeat

Updated: May 27, 2026

Before You Calculate

Gather these measurements:

Track or rod width — full width including returns (NOT window frame width)
Finished drop — from top of heading to bottom hem
Pleat style — determines fullness ratio
Fabric bolt width — check your fabric (typically 54” / 137 cm)
Pattern repeat — on the fabric bolt label (0 if solid or texture)

Step 1 — Calculate Cut Width Per Panel

Finished panel width = track width ÷ number of panels
Cut panel width      = finished panel width × fullness ratio + side returns × 2

Example: 120” track, 2 panels, pinch pleat (2.5×), 3” side returns each:

Finished panel width = 120 ÷ 2 = 60"
Cut panel width      = 60 × 2.5 + 3 + 3 = 156"

The side return (also called “return”) is the section of drapery that wraps from the rod back to the wall. Standard US return = 3”. Some rods require 4–6” depending on projection from the wall.

Step 2 — Calculate Widths Per Panel

Widths per panel = ⌈ cut panel width ÷ fabric bolt width ⌉

Always round UP to the next whole number. Never use a fraction of a width.

Widths = ⌈ 156 ÷ 54 ⌉ = ⌈ 2.89 ⌉ = 3 widths per panel

3 full widths of 54” fabric (= 162” total) are seamed together and then pleated to 60” finished width. The extra 6” is taken up in the pleats.

Step 3 — Calculate Cut Length

Without pattern repeat:

Cut length = drop + top heading allowance + bottom hem allowance

Standard allowances:

Top heading: 4” (stiffened with buckram)
Bottom hem: 8” (folded double = 4” visible hem)

Cut length = 96" + 4" + 8" = 108"

With pattern repeat:

Adjusted cut length = ⌈ raw cut length ÷ repeat ⌉ × repeat

For a 108” raw cut with an 18” repeat:

⌈ 108 ÷ 18 ⌉ × 18 = 6 × 18 = 108" (exact — no waste in this case)

For a 102” raw cut with an 18” repeat:

⌈ 102 ÷ 18 ⌉ × 18 = ⌈ 5.67 ⌉ × 18 = 6 × 18 = 108"
Waste per cut = 108 - 102 = 6"

Step 4 — Calculate Total Yardage

Total widths = widths per panel × panels per window × number of windows
Total inches = total widths × cut length
Total yards  = total inches ÷ 36

For the example (2 panels, 1 window):

Total widths = 3 × 2 × 1 = 6 widths
Total inches = 6 × 108 = 648"
Total yards  = 648 ÷ 36 = 18.0 yards
Total metres = 18.0 × 0.9144 = 16.46 metres

Step 5 — Add Lining (If Applicable)

Lining is cut with the same number of widths but a shorter cut length:

Lining cut length = drop + 4"   (simple hem only — no heading or bottom bulk)
Lining yards      = total widths × lining cut length ÷ 36

For the example:

Lining cut length = 96 + 4 = 100"
Lining yards      = 6 × 100 ÷ 36 = 16.67 yards

Calculating for Multiple Windows

If you have multiple identical windows in the same room, multiply total widths:

Total widths = widths per panel × panels × number of windows

For 4 matching windows (same size), multiply the single-window yardage by 4.

Important: When buying fabric for multiple windows, order all yardage from the same dye lot. Dye lots can vary by shade, which becomes visible when panels are side by side. For pre-calculated tables by window size and pleat style, see Drapery Yardage by Window Size.

Common Calculation Mistakes

Mistake 1: Using window frame width instead of track width

Track width includes the extension beyond the window frame. A 60” window with track extending 12” each side = 84” track width. Using 60” instead of 84” understimates yardage by 3–5 yards.

Mistake 2: Rounding widths down

Always round widths per panel UP. Rounding down leaves you 3–6” short in cut panel width — not enough to form proper pleats.

Mistake 3: Not adjusting for pattern repeat

Each cut must be usable from the same point in the repeat. Solid fabric: use exact cut length. Patterned fabric: round UP to next full repeat. Failure to adjust creates mismatched patterns at seam lines.

Mistake 4: Forgetting side returns

Returns add 3” (8 cm) to each side of the cut panel width. Without returns, the panel won’t wrap around the rod end to the wall — the gap shows.

Mistake 5: No safety margin

Always add 10% to your calculated yardage before ordering. Fabric comes in dye lots — ordering more later risks a mismatch.

Use the Drapery Yardage Calculator — it handles all five steps automatically.