How to Measure Your Windows for Curtains

Why Accurate Measurement Matters

Getting your curtain measurements right is the single most important step before ordering. Even the most beautiful fabric will look wrong if the curtains are too short, too narrow, or hung at the wrong height. The good news: measuring is straightforward once you know what to look for.

All you need is a steel tape measure, a pencil, and this guide.

What You'll Need to Measure

There are four key measurements for any curtain order:

1. Finished width — how wide the curtains will be when closed
2. Finished drop — how long the curtains will hang
3. Rod or track position — where you'll mount the hardware
4. Return — the distance from the rod bracket to the wall (for tracks and some rods)

Step 1: Decide Where to Mount Your Rod

Before measuring, decide where your rod or track will sit. This affects everything else.

• Height: For a classic look, mount the rod 10–15cm above the window frame. For a dramatic, ceiling-height effect, mount it 5–10cm below the ceiling — this makes the room feel taller.
• Width: Extend the rod 15–20cm beyond the window frame on each side (minimum). This allows the curtains to clear the glass when open and makes the window appear wider.

Step 2: Measure the Width

Measure the total length of your rod or track from end to end (not the window frame — the rod itself). This is your track/rod width.

Your curtain fabric width will need to be wider than this to allow for fullness. Your curtain supplier will calculate the fabric width based on your chosen fullness ratio — you just need to provide the finished (closed) width you want the curtains to cover.

Tip: If you have two curtain panels (one for each side), the combined finished width should equal the rod width plus a small overlap in the centre (usually 2–5cm per panel).

Step 3: Measure the Drop

Measure from the top of the rod or track down to where you want the curtain to end. There are three common drop options:

• Sill length: Curtain ends 1–2cm above the window sill. Practical for kitchens, bathrooms, and children's rooms.
• Below sill: Curtain ends 10–15cm below the sill. A neat, tailored look for most rooms.
• Floor length: Curtain ends 1–2cm above the floor. The most elegant option for living rooms and bedrooms.
• Puddle: Curtain extends 5–20cm onto the floor. A dramatic, luxurious look for formal spaces.

Important: Always measure from the top of the rod ring or eyelet (not the top of the rod itself) to get an accurate drop. The hook or ring adds height.

Step 4: Account for Header and Hem

Your curtain maker will add fabric above and below your finished measurements for the header (top) and hem (bottom). You don't need to calculate this — just provide your finished drop measurement and they'll handle the rest.

Common Measuring Mistakes to Avoid

• Measuring the window frame instead of the rod: Always measure from where the curtain will actually hang.
• Forgetting the fullness: Don't order curtains the same width as your window — they'll look flat and sparse. Your supplier will advise on fabric width based on fullness.
• Not accounting for floor clearance: For floor-length curtains, subtract 1–2cm from your measurement so the curtain doesn't drag.
• Measuring only once: Always measure twice. Windows are rarely perfectly square.

Measuring for Different Window Types

Bay Windows

Measure each section of the bay separately. You can use individual rods per section, or a continuous curved track that follows the bay.

Tall or Arched Windows

For arched windows, curtains typically hang from a rod above the arch, covering the full window including the arch. Measure from the rod to the floor as normal.

Patio Doors

Ensure the curtain stack back clears the door opening completely when the curtains are open. Extend the rod generously on both sides.

Use the Tessivra Measurement Tool

Not sure where to start? Our interactive measurement tool walks you through each step with visual guides, so you can measure with confidence and order knowing your curtains will fit perfectly.