A wallpaper-coverage calculator estimates the number of rolls needed for a room, accounting for wall area, pattern repeat, and waste. The Toolenza calculator uses 56 sq ft per single roll (the US standard, accounting for typical waste) — but most wallpaper today is sold as double rolls.

Roll types you'll see

• Single roll — nominally 28 sq ft (4 sq metres) of paper, ~56 sq ft of coverage rated by the manufacturer. Mostly historical; rare in stores now.
• Double roll — 56 sq ft of paper, ~104 sq ft of coverage. The default at most retailers — when a store says "a roll," they typically mean this.
• Euro/metric roll — 5.5 sq metres (~58 sq ft) of paper. Common for European imports; matches single-roll coverage with different dimensions.

Pattern repeat eats paper

If the wallpaper has a pattern, every strip has to start at the matching point of the previous strip. A half-drop repeat wastes about half the repeat distance per strip; a straight repeat wastes less. Practical impact:

• Small repeats (< 6 in) — waste roughly 10–15%.
• Medium repeats (6–18 in) — waste 15–25%.
• Large repeats (> 18 in) — waste 25–40%. Add an extra roll for safety.

How to measure

1. Perimeter of the room in feet.
2. Wall height in feet (typically 8 or 9).
3. Subtract doors and windows — most are 20 sq ft each.
4. Multiply for total square feet.
5. Divide by 56 (single) or 104 (double) for the roll count.
6. Round up and add at least 1 extra roll.

Pro tips

• Buy from one batch. Like tile, dye lots vary. Order the entire room's worth at once.
• Pre-paste, paste-the-wall, peel-and-stick — three different application methods. Easy beginner choice: paste-the-wall or peel-and-stick.
• Take off light switch covers and outlet plates before papering. Patching around them looks amateur.