How the wallpaper calculator works
How much does a roll of wallpaper cover?
A standard American single roll holds roughly 28–35 square feet, but trimming and matching the pattern use some of it. Sherwin-Williams' guidance is to count on about 25 usable square feet per single roll. Large pattern repeats waste more paper because each strip has to be shifted to line up with the next.
Single vs. double rolls
Most US wallpaper is priced per single roll but packaged as a double roll (one continuous piece twice as long). A double roll gives you fewer seams and less waste per strip, which is why it is the standard.
Buying tips
- Buy all rolls from the same run (batch or lot) number — colors vary between runs.
- Get one extra roll for repairs and mistakes, especially with large patterns.
- Peel-and-stick wallpaper lists its own coverage per roll; enter it as the usable square footage.
Sources
Frequently asked questions
How many rolls of wallpaper for a 12x12 room?
With 8 ft walls, one door and two windows, the walls are 333 sq ft — 14 single rolls (7 double rolls) for a small or no pattern repeat.
How many square feet are in a double roll?
About 56 square feet nominal, or roughly 50 usable square feet after trimming and matching.
Should I subtract windows and doors?
Yes for an accurate count, but buy an extra roll for patterns with a large repeat.