Valance Size for Window Calculator
Find the right valance width, drop, and fabric cut size for any window.
📈 Valance presets
⚙ Window sizing inputs
🎨 Valance style guide
Tailored linen
Best for light window dressing and small headers.
Gathered cotton
Balances softness and structure for an easy bedroom or guest room finish.
Classic valance
Gives a tailored but relaxed drape with enough body for crisp folds.
Lined blackout
Needs a little more width so the face hangs cleanly.
📑 Window span references
| Window span | Valance width | Drop | Fit |
|---|---|---|---|
| 24-36 in | 32-44 in | 10-12 in | Narrow |
| 36-48 in | 44-58 in | 12-14 in | Balanced |
| 48-72 in | 60-84 in | 14-16 in | Classic |
| 72-96 in | 88-112 in | 16-18 in | Wide |
| Style | Fullness | Feel | Use case |
|---|---|---|---|
| Tailored | 1.5x | Clean | Small spans |
| Balanced | 1.75x | Soft | Guest rooms |
| Classic | 2x | Full | Most windows |
| Plush | 2.5x | Deep | Layered rooms |
| Fabric width | Span guide | Panels | Notes |
|---|---|---|---|
| 45 in | Up to 36 in | 1 | Narrow topper |
| 54 in | Up to 48 in | 1-2 | Common width |
| 58 in | Up to 60 in | 2 | Neat split |
| 60 in | 60 in+ | 2-4 | Wide coverage |
| Window width | Return | Finished width | Comment |
|---|---|---|---|
| 24-36 in | 4 in | 32-44 in | Compact frame |
| 36-48 in | 5 in | 46-58 in | Balanced look |
| 48-72 in | 6 in | 60-84 in | Standard span |
| 72-96 in | 8 in | 88-112 in | Wide window |
💡 Practical sizing tips
Use the calculator to fine-tune the valance width, drop, and total yardage before you cut fabric. The breakdown shows both the selected sizing and the construction math.
📝 Quick summary
A window valance looks best when the width carries a little extra return, the drop lands cleanly, and the fabric width is rounded up for clean sewing.
Find the right size for window valance commonly is difficult. It should hang half to two inches past every side of the window in its final state. Like this for 40-inch window, you need 41 to 44 inches of valance up.
At 36-inch window, add 2 to 4 inches on every side works well, with less for narrower and more for wide windows.
How to Find the Right Size for a Window Valance
A helpful chart helps to count how many valance panels you need. Windows to 29 inches wide need 1 valance. Those of 30 to 39 inches need 2 valances.
For 40 to 48 inches, 2 to 3 valances work. Windows in 49 to 72 inches want 3 to 4, and 73 to 96 inches need 4 to 5. Really wide windows of 97 to 120 inches need 5 to 6 valances.
You commonly use several panels to get the wanted fullness, even at one window. Any valance can give the wanted look.
For full valance curtain without sheer, you add at least 12 inches to the width of the window (6 inches on every side)… To get the right width. Some double or triple the window width for extra fullness.
Now about the length. Usually valance lengths fall have 18 to 35 inches. They should cover only to 6 inches of the window top.
The measurements include the rod pocket, so measure from the rod. Valances with outside mount have typical drop of 17 to 21 inches on walls with 8-foot ceilings, and that length grows with the ceiling height.
18-inch drop that mounts two inches above the window trim, lay the valance in 1/5 of the distance from its top to the floor. Valance must not be 1/3 or 1/4 of the window height. The Golden Mean or Fibonacci rule commonly gives better proportions.
Shaped valances and cornices need more change between short and long points when they become longer. At very tall 20-foot windows, 30-inch long point on cornice looked perfect after installation, although it seemed too big before. On huge window of 100 inches wide and 75 inches tall, mistakes in size can make the valancesilley.
When you hang valances over blinds, attach the rod flat to the wall anchors, especially on drywall. Decorative curtain rod works when the valance sits in full width. Swag valance with jabots in solid color add character without too much formality.
DIY cornice boards are other choice, and some use velcro tape to change the fabric by seasons.

