Wallpaper Calculator
Find out how many rolls of wallpaper a room needs, including an allowance for pattern repeats.
How this calculator works
We calculate wall area from your room's dimensions, subtract average door and window openings, add a pattern-repeat waste allowance, then divide by the usable coverage of one roll.
Works in feet or meters. A standard US double roll covers about 56 sq ft (5.2 sqm) after trim — adjust the roll-coverage field if your product's label states a different figure.
All calculations run in your browser only — nothing you type is sent to a server. Results are estimates for planning purposes; always round up and buy a small surplus for cuts, waste, and future repairs.
Example calculations
12 × 10 ft room, 8 ft ceilings, 1 door, 1 window, 15% waste
≈ 285 sq ft to cover → 6 rolls.
Large pattern repeat (24 in+), same room
Increase waste to 20–25% — large repeats need more trimming per strip.
Frequently asked questions
Why does pattern repeat matter so much?
Every strip has to line up with the one next to it. A large pattern repeat means more of each roll gets trimmed away to keep the pattern matched, so it needs a bigger waste allowance than plain or small-repeat wallpaper.
Is a 'double roll' the same as two single rolls?
Not quite in usable coverage — a double roll is one continuous longer roll, which usually wastes less than two separate single rolls because there are fewer seams to match.
Should I buy extra for future repairs?
Yes — buy at least one extra roll from the same dye lot for future patch repairs, since wallpaper is often discontinued or re-dyed differently in later print runs.