Wallpaper Calculator

To calculate wallpaper rolls needed:

• Measure the room perimeter (length + width) x 2
• Multiply by wall height to get total wall area
• Subtract area for doors (~20 sq ft each) and windows (~15 sq ft each)
• Calculate roll coverage (roll width x roll length)
• Divide usable wall area by roll coverage
• Round up to the nearest whole roll and add 10% extra

Pattern repeat is the vertical distance between where a pattern begins and where it repeats. This matters because:

• More waste: You need to cut strips to align patterns, creating more waste
• Longer repeats = more waste: A 24" repeat creates more waste than a 6" repeat
• Random match patterns: Have no repeat and create minimal waste
• Straight match: Patterns align horizontally across strips
• Drop match: Patterns offset by half the repeat, creating even more waste

This calculator adds a waste factor based on your pattern repeat length.

Common wallpaper roll sizes include:

• US Single Roll: 20.5" wide x 33 ft long (~56 sq ft)
• US Double Roll: 21" wide x 16.5 ft long (~29 sq ft)
• Euro Standard: 20.8" wide x 34.5 ft long (~60 sq ft)
• Commercial: 27" wide x 27 ft long (~61 sq ft)

Always check the roll dimensions on your specific wallpaper before ordering.

We recommend purchasing 10-15% extra wallpaper to account for:

• Pattern matching and alignment waste
• Cutting around outlets, switches, and corners
• Mistakes during installation
• Future repairs if the wallpaper gets damaged
• Dye lot variations if you need more later

Wallpaper from different batches may have slight color variations, so it is best to buy enough from the same dye lot.

Yes, you should subtract the area of doors and windows, but with some caveats:

• Standard doors: Subtract approximately 20 sq ft each
• Standard windows: Subtract approximately 15 sq ft each
• Small windows: Some installers do not subtract small windows as the wallpaper around them often cannot be used elsewhere
• Complex openings: May create more waste than saved, especially with patterned wallpaper

When in doubt, be conservative with deductions to ensure you have enough wallpaper.