How to Choose the Right Curtain Size for Your Window
Buying curtains the exact same width as your window results in flat, unattractive folds and poor light blocking. The standard rule is to buy curtains that are 1.5 to 2 times the window width. For a full, luxurious look, go up to 2.5 times. If you're hanging two panels, divide the total width by 2 to get the size for each panel.
How to Calculate Curtain Length
Install your curtain rod about 10–15 cm above the window frame — this makes the window appear taller and lets in more light when the curtains are open. Measure from the rod down to the floor and subtract 1–2 cm for clearance. Some styles intentionally pool on the floor by 5–10 cm for a dramatic, formal look.
Blackout Curtain Sizing Tips
To maximize light blocking, blackout curtains should extend 5–10 cm beyond each side of the window frame and 5–10 cm above and below. Even small gaps around the edges can let in significant light. Installing the rod close to the wall and using curtain returns (end panels that wrap to the wall) further improves blackout performance.
Shrinkage Allowance by Fabric Type
Cotton and linen curtains can shrink 3–5% when washed. Buy 5–10 cm longer than your measurement to account for shrinkage. Polyester and synthetic fabrics shrink very little, so you can buy to exact measurements with confidence.
Frequently Asked Questions
1.5–2.0× the window width for standard folds; 2.5× for full, luxurious folds. Divide total width by 2 for two-panel sets.
Yes. Extend 5–10 cm on each side and top/bottom to prevent light leakage around the edges.