Curtain Size Calculator — Free Online Curtain Size Calculator

Find the right curtain width and length for your window. 100% free, no signup.

Total curtain width
0 in
Panels (each ~50 in)0
Rod width (add 8–12 in)0 in
Suggested drop0 in

What size curtains do I need?

For a gathered, full look, curtains should total about two times your window width. Divide that by the width of one panel (usually ~50 in) to get the number of panels, and hang the rod 8–12 inches wider than the window so the curtains clear the glass when open.

Redesign the whole room, not just the numbers

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Frequently asked questions

How wide should curtains be?

Aim for roughly 2× the window width combined so they look full when closed. A 48-inch window wants about 96 inches of curtain across two panels.

How high should I hang the rod?

Hang it 4–6 inches above the window (or near the ceiling for a taller look) and 8–12 inches wider than the frame on each side.

Want to preview the look?

Download RoomGPT free and see new curtains, colors and full redesigns on a photo of your real room.