Curtain Fabric Calculator — Metres for any window
Total fabric metreage for any window, factoring in fullness ratio, hem allowance and curtain header style.
Quick answer
For a 6 ft × 7 ft window with 2× standard pleat: approximately 7.5 metres of 48-inch wide fabric, or 5 metres of 54-inch wide fabric. Order lining at the same metreage if using blackout drapes.
Window & curtain
Fabric needed
7.5m
For 6 ft window with 2× fullness
Total panel width12 ft (366 cm)
Drops needed3 drops
Per drop2.5 m
Estimated cost₹3,375
How curtain fabric is calculated
Curtain fabric isn't just window-width × height — you need extra width for fullness (so the curtain looks pleated, not flat) and extra length for hems and the header. Then divide by fabric width to find how many vertical "drops" you need to cut.
Formula: Total fabric (m) = Drops × (curtain drop in m + hem allowance), where Drops = ⌈(window width × fullness × 12) ÷ fabric width in inches⌉
How to use this calculator
- Measure the window width (or rod width if it extends past the window) and your desired curtain drop (height) in feet.
- Pick a fullness ratio. 2× is standard pleated. Sheers can be 1.5×; luxurious pinch-pleated drapes use 2.5×.
- Pick the fabric width from the bolt — Indian standard is 48 inches.
- Pick the hem allowance — standard is 20 cm (10 cm header + 10 cm bottom hem).
Fullness ratio reference
| Fullness | Look | Best for |
|---|---|---|
| 1.5× | Lightly gathered | Sheers, café curtains |
| 2.0× | Standard pleat | Most living & bedroom curtains |
| 2.5× | Rich pleating | Pinch-pleat, formal drapes |
| 3.0× | Theatrical fullness | Goblet pleats, heavy velvet |
Frequently asked questions
How much fabric for 6 ft wide curtains?
For a 6 ft wide window with standard 2× fullness and 7 ft drop, you need about 7.5 metres of 48-inch wide fabric (or 5 metres of 54-inch wide fabric).
What is curtain fullness ratio?
Fullness ratio is how much wider the curtain panel is than the window. 1.5× is light/sheer, 2× is standard, 2.5× is luxurious for heavy drapes. Higher fullness means more fabric and richer pleats.
Should I buy lining separately?
Yes — calculate lining at the same metreage as the main fabric. Most blackout linings come in 54-inch widths, which may save you a drop compared to narrower fashion fabrics.
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