Wallpaper Calculator
Calculate exactly how many rolls of wallpaper you need for your room. Our calculator accounts for pattern repeats and waste.
How to Use This Calculator
- Measure the width and height of each wall you plan to wallpaper
- Enter the total number of walls (typically 4 for a room)
- Check your wallpaper roll for width (usually 21" or 27") and length (typically 33')
- If your wallpaper has a repeating pattern, enter the pattern repeat distance
- Subtract any large windows or doors from the total area
How We Calculate Wallpaper
Total Wall Area: Width × Height × Number of Walls
Usable Area: Total Area - Windows/Doors
Roll Coverage: (Roll Width ÷ 12) × Roll Length
Rolls Needed: Usable Area ÷ Roll Coverage × Waste Factor
The waste factor is 1.1 (10%) for solid colors and 1.2 (20%) for patterns to account for matching and trimming.
Frequently Asked Questions
How much extra wallpaper should I buy?
We recommend 10-15% extra for solid colors and 15-20% for patterns. Our calculator already includes this allowance.
What is pattern repeat?
Pattern repeat is the distance between where a pattern repeats on the wallpaper. It's important for matching patterns across strips.
Should I subtract windows and doors?
Only subtract large windows and doors. Small windows and standard doors are often left in the calculation as a buffer.
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