Curtain Fabric Table: Fabric needed by Window/track width
Reference table of fabric needed for Curtain Fabric across a range of window/track width values — exact, engine-computed figures you can read off at a glance.
Curtain Fabric Calculator
Verified formula Updated Jun 2026 Private — runs on your device
Verified formula
Private
Fabric needed
7.50
- Fabric widths (drops)
- 3
For general information only — not financial, tax, legal or medical advice. Verify before you rely on it.
How to use the Curtain Fabric Calculator
The Curtain Fabric Calculator works out your fabric needed, along with 1 related figure in an instant. Enter window/track width, fullness ratio and fabric roll width and the result updates as you type — it is free, needs no sign-up, and runs entirely in your browser so your figures stay private.
- Enter the window/track width.
- Enter the fullness ratio.
- Enter the fabric roll width.
- Enter the finished drop (incl. hems).
- Read off your fabric needed, together with fabric widths (drops) — the calculator updates automatically, with no button to press.
Worked example
For example, with window/track width of 2 m, fullness ratio of 2, fabric roll width of 1.4 m and finished drop (incl. hems) of 2.5 m, the fabric needed is 7.50.
| Window/track width | 2 m |
|---|---|
| Fullness ratio | 2 |
| Fabric roll width | 1.4 m |
| Finished drop (incl. hems) | 2.5 m |
| Fabric needed | 7.50 |
|---|---|
| Fabric widths (drops) | 3 |
Results are estimates for educational use, not professional advice.
Key terms explained
- Ratio
- A comparison of two quantities showing how many times one contains the other.
Frequently asked questions
Find the number of fabric widths (window width × fullness ÷ fabric width, rounded up), then multiply by the drop. A 2 m window at 2× fullness needs 3 widths of 2.5 m, or 7.5 m.
It is how gathered the curtains look. A ratio of 2 means twice the track width in fabric, giving a generous wave.
Yes. Include hems in the drop and add extra length to match patterns across widths.
Fabric comes in fixed roll widths, so you buy whole drops and join them to reach the gathered width.
Enter the window/track width. Enter the fullness ratio. Enter the fabric roll width. Enter the finished drop (incl. hems). Read off your fabric needed, together with fabric widths (drops) — the calculator updates automatically, with no button to press.
Related guides
How to Calculate Curtain Fabric: Formula, Steps & Examples
Learn how to calculate Curtain Fabric — the formula explained step by step, with worked examples and a free calculator to check your answer.