Calculadora de Papel de Parede
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
área = perímetro × pé-direito − portas_janelas; rolos = ceil(área / cobertura)
About this calculator
This calculator helps determine how many rolls of wallpaper are needed to cover a room. Simply enter the wall dimensions (width and length), ceiling height, roll coverage, and subtract the area of doors and windows. The result is rounded up, as rolls cannot be bought in fractions.
The calculation has three steps: first, compute the room perimeter (sum of all walls). Multiply by ceiling height to get total wall area. Then subtract door and window area. Finally, divide the net area by the roll coverage and round up. This method avoids waste or shortage.
Use this calculator when planning decoration for a bedroom, living room, or office. It is useful for both professionals and DIY renovators. Remember to measure accurately and consider a little extra for fitting and repeating patterns. The tool speeds up budgeting and prevents wrong purchases.
Cautions: ensure measurements are in consistent units (meters or centimeters). Correctly deduct door and window areas. For patterned wallpaper requiring alignment (rapport), actual coverage may be lower. Also consider that rolls may have different widths; the calculator uses the coverage you enter.
Frequently asked questions
How do I measure the room perimeter?
Measure the width of each wall and add them up. For a rectangular room, add length and width and multiply by 2.
Do I need to deduct doors and windows?
Yes, to avoid buying extra rolls. Measure height and width of each opening and subtract the total area from the wall area.
What is roll coverage?
It is the area a roll covers, usually stated on the package. For example, a roll 0.53 m wide by 10 m long covers 5.3 m².
What if the wallpaper has a pattern that needs matching?
In that case, the actual coverage may be lower. Consider buying an extra roll to ensure the pattern aligns correctly.
Can I use the calculator for peel-and-stick wallpaper?
Yes, as long as you enter the correct roll coverage. The principle is the same.