How the calculator works
Wallpaper is hung in vertical strips, so the useful question is not "how many square feet?" but "how many full-height strips do I need, and how many come out of one roll?"
- Strips per wall: wall width divided by roll width, rounded up.
- Strip length: the tallest wall height plus a few inches for trimming plus the pattern repeat (one and a half repeats for drop matches), because each strip has to start at the same point in the pattern.
- Strips per roll: roll length divided by strip length, rounded down — the leftover piece is usually too short to use.
- Rolls: strips needed divided by strips per roll, rounded up, plus a spare.
Why add a spare roll?
Pattern waste varies from wall to wall, mistakes happen, and a roll from the same batch is the only way to make invisible repairs later. Read more in how to order wallpaper.
When the calculator is not enough
Stairwells with angled walls, ceilings, rooms with many windows and murals ordered to size need a measured estimate. Murals are ordered by wall size, not by roll — see mural vs repeating wallpaper. We can measure as part of the estimate.
This calculator gives an estimate for planning. Always check the manufacturer's instructions and confirm quantities before ordering; we review quantities as part of every estimate.