How to Measure for Curtains: Width, Length and Placement

Home decor · Measure first, order once

Curtains are surprisingly good at exposing a small measuring mistake. Two inches too short and they look as though they outgrew the room. Too narrow and closing them becomes a negotiation.

Learning how to measure for curtains comes down to three decisions: where the hardware will sit, how much fabric you want across it, and where the hem should end. Make those decisions in that order. The window itself is only part of the calculation.

1. Choose the rod position before measuring the fabric

Use a metal tape measure, a pencil and a notebook. Measure each window separately, even if they look identical. Houses enjoy having opinions about symmetry.

Record the outside width of the window frame. Then look at the wall beside it: is there enough space for the open curtains to stack without covering most of the glass? Check nearby walls, cabinets, door openings and electrical fittings before deciding how wide to go.

IKEA’s measuring guide suggests allowing at least 6 inches on each side for fabric curtains. Treat that as a starting allowance, not a promise that every thick blackout curtain will stack into that space. Wider panels and bulkier fabrics may need more room.

Choose the height next. A rod above the window can make the arrangement feel taller, but there is no compulsory distance that suits every room. Check the ceiling, trim and bracket requirements. If the hardware is already installed, measure it rather than planning around a different imaginary rod.

2. Calculate the combined curtain width

Measure the usable part of the rod between the decorative ends, or the working length of the track. This is the span the curtains need to cover. Decorative finials do not need their own fabric allowance.

For flat ready-made panels, multiply that span by your chosen fullness. Twice the span gives you fabric that can form folds when closed rather than stretching like a bedsheet across the window. Fabric weight and heading style can change the best ratio, so use the curtain maker’s instructions when supplied.

For example, an 80-inch rod with a two-times fullness target needs about 160 inches of flat fabric. Two 52-inch panels provide 104 inches in total, which will cover the rod but look relatively flat when drawn. Four provide 208 inches, giving a fuller result but a larger stack at each side. Two wider panels may be a neater option if available.

Do not apply that calculation blindly to made-to-measure pinch-pleat curtains. A seller may quote the finished, gathered width and already account for fullness. Multiplying it again could leave you with enough fabric to curtain a modest theater.

3. Measure from the correct hanging point

The drop starts where the curtain actually hangs, not automatically at the top of the window. Rings, hooks, rod pockets and grommets position the fabric differently. Read the product’s measuring diagram and include any fabric that sits above the rod.

Measure the drop at the left, middle and right. Floors and ceilings are not always perfectly level. Decide whether you want the curtain to clear the highest point of the floor, touch it lightly, or deliberately pool. For curtains opened every day, a small clearance is usually easier to live with than a fabric puddle that collects dust.

If a standard panel is slightly too long, hemming may solve it. If it is too short, moving the rod down changes the whole arrangement and may reduce window clearance. Check the care label before altering washable curtains; follow any prewashing instructions so you are not hemming fabric that will later shrink.

A complete measuring example

Imagine a window frame 60 inches wide with clear wall space on both sides. You choose a 76-inch usable rod, leaving 8 inches beyond the frame at either end. The selected panels are flat, and the maker recommends about twice the rod width.

1. Width target: 76 × 2 = 152 inches of combined panel width.
2. Panel choice: two 76-inch-wide panels meet that target. Two 50-inch panels do not.
3. Drop: after accounting for the heading, the intended hanging point to hem measures 95 inches.
4. Length choice: compare a suitable longer panel that can be hemmed with made-to-measure options. Check the finished length convention before buying.

These are example measurements, not a recommended setup for every 60-inch window. Your fabric, wall space and hardware determine the finished result.

The last checks before checkout

• Write every measurement in the same unit. One inch equals 2.54 centimeters.
• Confirm the number of panels in the package.
• Check heading compatibility with the rod or track.
• Check the bracket load rating for the combined curtain weight.
• Allow enough space behind the fabric for handles and trim.
• For blackout curtains, consider light gaps at the top, center and sides as well as the fabric itself.

If drilling is restricted, compare the limitations in our no-drill window covering guide before choosing hardware. A mounting method that holds a lightweight blind may not support a heavy pair of curtains.

Common curtain-measuring questions