Curtain Size Calculator
Plan custom or ready-made curtains by entering window measurements, fullness, and how high you mount the rod.
Total width
90.0"
Each panel about 45.0" wide
Finished length
56.0"
Mount rod ~6.0" above the window
Tieback placement
Position tiebacks about 33.3" from the bottom edge.
How to Use This Calculator
Measure the window area
Note the width you want to cover and the distance from the rod to your desired hem.
Pick fullness and mount style
Choose a fullness multiplier and decide if the curtains end at the sill, apron, floor, or puddle.
Review panel recommendations
Use the total width and panel width to plan custom sewing or confirm ready-made sizes.
Formula
Total width = Window width x Fullness
Single panel width (two panels) = Total width / 2
Finished length = Window height + Rod height above window + Mount style allowance
Example: 60 inch window, fullness 1.8, rod 6 inches above, floor length mount → total width 108 inches, panels about 54 inches each, finished length 56 inches.
Full Description
Properly sized curtains frame the window, add softness, and help control light. This calculator translates interior design guidelines into actionable measurements so your panels look intentional instead of accidental.
Tweak fullness to match fabric weight, mount rods higher to make ceilings feel taller, and choose puddling for drama or sill length for casual kitchens. The results equip you to buy or sew with confidence.
Bring the numbers when shopping for ready-made panels or estimating custom sewing so every window in your home gets the tailored treatment it deserves.
Frequently Asked Questions
How wide should curtains be?
Plan for 1.5 to 2 times the window width for pleated or grommet panels. Sheers or very full drapes may go up to 2.5 times.
How high should I hang the rod?
Mount 4 to 6 inches above the window frame, or halfway between the frame and ceiling, to make the room feel taller.
Should curtains touch the floor?
Floor-length is standard. For a modern look, let them kiss the floor; for a romantic look, add a 2 inch puddle.
Can I use ready-made panels?
Yes. Match the calculator’s width and length to store sizes. You may need two panels per side for adequate fullness.
What about pattern repeats?
Add extra length if your fabric has a vertical repeat so patterns align across multiple panels.