Wallpaper Calculator
Estimate wallpaper rolls for a room by wall area, roll coverage and pattern repeat.
How to use this tool
- Enter room perimeter and ceiling height.
- Set roll width and length (or use standard).
- Set pattern repeat in inches.
- Set wastage and cost per roll.
- Calculate rolls and cost.
How it works
Total area = perimeter x height. Net coverage per roll = roll area / (1 + repeat waste). Rolls = area / net coverage, rounded up.
Tips
- Pattern repeats above 24 in can waste 20%+.
- Vertical stripes usually have no repeat waste.
- Buy the same dye lot across all rolls.
Limitations
Textured, large-repeat or diagonal-paste wallpapers need extra beyond this estimate.
Frequently asked questions
How many sq ft does a roll cover?
A standard 20.5 in x 33 ft roll covers about 56 sq ft. Working area after trimming is less — the calculator applies pattern-repeat waste.
What is a pattern repeat?
The vertical distance before the pattern repeats. Matching patterns wastes 0–15% of each roll; the calculator includes this.
Should I subtract windows and doors?
Generally no — openings' offcuts are usually unusable for matching elsewhere. Add them only if the room has very large windows.