Free Wallpaper Rolls Calculator
Calculate the number of wallpaper rolls needed for a room based on wall dimensions, pattern repeat, and window/door deductions.
Rolls Needed
8 rolls
Rolls Needed vs Room Perimeter
How to Calculate Wallpaper Rolls
Formula
Net Wall Area = (Perimeter x Height) - Openings Area
Usable Coverage per Roll = Roll Length x (Roll Width / 12) x Efficiency
Rolls Needed = ceil(Net Wall Area / Usable Coverage per Roll)
Efficiency is typically 90% for solid or random patterns and 80% for patterns with a repeating motif. The repeat causes waste because each strip must be aligned to the pattern.
Standard Roll Sizes
American single rolls: 21 in wide x 33 ft long (about 57 sq ft gross). European rolls: 21 in wide x 33 ft long. Double rolls are twice the length.
Example Calculation
A room with 52 ft perimeter, 8 ft ceilings, 40 sq ft of openings, standard 21-inch rolls at 33 ft, no pattern repeat.
- 01Gross wall area = 52 x 8 = 416 sq ft
- 02Net area = 416 - 40 = 376 sq ft
- 03Coverage per roll = 33 x (21/12) x 0.90 = 51.97 sq ft
- 04Rolls needed = ceil(376 / 51.97) = 8 rolls
Frequently Asked Questions
Learn More
How to Calculate Concrete Needed for Any Project
Learn how to calculate the exact amount of concrete needed for slabs, footings, columns, and other projects. Covers volume formulas, waste factors, and ordering tips.