Curtain Size Calculator

Find the right rod width, panel width, and panel length — with fullness and standard size suggestions.

Fast defaults below. Use Advanced options only if you want to fine-tune. Click Calculate for results.

Inside trim-to-trim window width.

Measure from where the rod will sit down to the floor.

We auto-set fullness; adjust in Advanced if needed.

Most windows use 2 panels.

Advanced Options (optional)

Imperial is typical for U.S. measurements. Metric is available for convenience.

Typical: 3–6 in each side.

Drop style uses inch presets: hover (−0.5"), kiss (0"), break (+1"), puddle (+6").

Used to suggest a fullness multiplier (if you want).

Typical: 1.5×–2× (grommet/rod pocket), 2×–2.5× (pleated), 2×+ (sheer).

Used to estimate how many ready-made panels will achieve your desired fullness.

Standard lengths: 63, 84, 95/96, 108, 120 inches.

If enabled, we’ll show the other unit system in parentheses.

Tip: The main calculator auto-sets fullness based on Curtain Style. If you change Fullness manually, your manual value is used.

Curtain Size Calculator — Get the Perfect Fit

Use our free Curtain Size Calculator to quickly determine the right rod width, curtain panel width, and panel length for your windows. Enter your window width, rod-to-floor height, side extensions, heading style, and fullness. The calculator estimates per-panel width, total coverage, and suggests the nearest U.S. standard curtain lengths so you can shop confidently online or in-store.

How to Measure for Curtains

  1. Measure window width: Inside trim to inside trim.
  2. Choose rod extensions: Add 3–6 inches beyond each side to let panels stack off the glass.
  3. Find rod height: Decide where you’ll mount the rod (often 4–6 inches above the window or higher for a taller look).
  4. Measure rod to floor: From the rod location straight down to the floor.
  5. Select a drop style: Hover, kiss, slight break, or puddle.
  6. Pick fullness: 1.5×–2× for grommet/rod-pocket, 2×–2.5× for pleated, 2×+ for sheers.

Common U.S. Curtain Sizes

Ready-made lengths: 63″, 84″, 95/96″, 108″, 120″. Ready-made panel widths are commonly 50–54″ each.

If your ideal length falls between sizes, choose the next longer length and hem, or opt for custom panels.

Tips for a Professional Look

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Frequently Asked Questions

What fullness should I choose for curtains?

For a balanced look, use 1.5× to 2× fullness for grommet and rod-pocket curtains, and 2× to 2.5× for pleated styles. Sheer fabrics often look best at 2× or more.

What are common U.S. curtain lengths?

Popular ready-made lengths are 63″, 84″, 95/96″, 108″, and 120″. If your ideal length falls between sizes, size up and hem or choose the next longer length.

How far should the rod extend past the window?

A typical guideline is 3–6 inches past each side of the window. Extending the rod makes the window appear larger and helps stack back the curtains without blocking light.

How high should I mount the rod?

Mounting the rod 4–6 inches above the window is common. For a taller, more dramatic look, mount closer to the ceiling. Measure from the rod position down to the floor for accurate panel length.

Important Estimate Disclaimer

Results are provided for general planning and budgeting purposes only. Actual coverage may vary based on surface condition, layout complexity, waste allowance, and product specifications.

Refer to our Methodology and Data Sources for calculation assumptions.

Surface preparation, substrate irregularities, and installation methods may increase required material quantities.