Wallpaper Calculator
Calculate how many rolls of wallpaper you need based on room dimensions, doors, windows, roll size, and pattern repeat.
Room and roll dimensions
Use 0 for solid or random-match wallpaper. Check the roll label for the repeat length.
Wallpaper needed
9 rolls
Includes a 10% waste allowance for trimming and pattern matching (raw need: 8 rolls).
Wall area
381 sqft
Total strips needed
31
Strips per roll
4
Rolls (no waste)
8
Frequently Asked Questions about the Wallpaper Calculator
What is the difference between single and double rolls?
A single roll (American) covers about 28 sqft; a double roll (European/standard) is twice as long (typically 33 ft) and covers around 56 sqft. Most wallpaper today is sold as double rolls because they yield more usable strips and reduce waste at ceilings.
How does pattern repeat affect how much wallpaper I need?
A pattern repeat is the vertical distance before the design starts over. You must add that distance to each strip so adjacent strips line up. A 24 inch repeat on an 8 ft wall can effectively waste 2 ft per strip, often pushing the order up by 1 to 2 extra rolls.
In what order should I hang wallpaper strips?
Start in an inconspicuous corner (behind a door) and work your way around the room in one direction. The last strip will overlap the first, so any pattern mismatch is hidden. Always hang from ceiling to floor and trim excess at the baseboard.
Should I subtract doors and windows from my wall area?
Yes, but only large openings. This calculator subtracts 21 sqft per door and 15 sqft per window. For small windows or many openings, measure them individually for a more accurate estimate.
Why does the calculator add 10 percent waste?
Real-world hanging involves trim cuts, mistakes, pattern matching errors, and damaged strips. The 10 percent buffer ensures you have enough from the same dye lot. Ordering a second batch later often results in slight color differences.