Curtain Size Calculator
Curtains that are too narrow look skimpy; panels that are too short look unfinished. Enter window width and height, choose fullness and length style, and get a planning estimate before you shop.
Final orders should use measurements taken after the rod is installed whenever possible—trim depth and ceiling height vary.
How it works
Total fabric width equals window width × fullness (commonly 1.5–2.5×). Length uses a typical rod height a few inches above the trim, then adjusts for sill, apron, floor clearance, or puddle styles.
Important limitations
Does not account for blackout linings, grommet vs pinch-pleat header take-up, or very tall ceilings. Always verify with product specs.
What to do next
Measure twice with a tape measure, decide rod placement, then read the curtain measuring guide before ordering.
Frequently asked questions
- How wide should curtains be?
- A common rule is 1.5–2.5 times the window width for fullness when closed. Two panels are typical for wider windows.
- How long should curtains be?
- Floor-length with a slight clearance is popular in living rooms; sill or apron lengths suit kitchens and busy areas. Measure from the rod, not only the window.
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