Wallpaper Calculator — How Many Rolls?
Enter your room size, wall height, and roll dimensions to get how many rolls of wallpaper you need, accounting for the pattern repeat.
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How it works
strips = ceil(perimeter ÷ roll width); strips per roll = floor(roll length ÷ (height + repeat + trim)); rolls = ceil(strips ÷ strips per roll)
Wallpaper rolls by room size (8 ft ceiling, no repeat, double roll)
| Room size | Wall perimeter | Double rolls |
|---|---|---|
| 10 × 10 ft | 40 ft | 8 |
| 10 × 12 ft | 44 ft | 9 |
| 12 × 12 ft | 48 ft | 10 |
| 12 × 16 ft | 56 ft | 11 |
| 14 × 16 ft | 60 ft | 12 |
| 16 × 20 ft | 72 ft | 15 |
For a standard 20.5-inch-wide double roll (~33 ft / ~56 sq ft) and no pattern repeat. A pattern repeat adds waste — enter yours above. No deduction for doors and windows, so it runs slightly generous.
Frequently asked questions
How many rolls of wallpaper do I need for a room?
For a 12×12 room with 8 ft ceilings and no pattern repeat, about 10 standard double rolls. Measure the wall perimeter, divide by the roll width to get the number of strips, then figure how many full strips you get per roll.
How does a pattern repeat affect how much wallpaper I need?
A pattern repeat means each strip is cut to match the one beside it, wasting up to a full repeat per strip. A large repeat (18+ inches) can add 25% or more. Enter your repeat above and the estimate includes it.
What is the difference between a single and double roll?
Wallpaper is priced as single rolls but usually packaged as double rolls — two singles on one bolt, about 56–60 sq ft. Double rolls give longer continuous runs and less waste, so this calculator estimates double rolls.