RemodelCalc

Wallpaper Calculator

Wallpaper is hung in drops (full-height strips). The pattern repeat decides how much of each roll is lost matching one drop to the next, so this counts drops rather than dividing square feet.

Feature wall, or the room perimeter
US double roll 20.5", Euro roll 20.5"/53 cm
US double roll 33 ft; Euro roll 10 m ≈ 32.8 ft
0 for plain or random match

How this calculator works

  1. Cut length = wall height rounded up to a whole number of pattern repeats, plus 4 inches for trimming.
  2. Drops per roll = roll length ÷ cut length, rounded down; the leftover is waste.
  3. Rolls = drops ÷ drops per roll, rounded up, plus one spare.

Wallpaper questions

What is a pattern repeat?

The vertical distance before the pattern starts again. A 21 inch repeat means every drop must start at the same point in a 21 inch cycle, so up to 21 inches can be lost per drop.

What is a drop match or half-drop?

In a half-drop match the pattern lines up halfway down on the next strip. It uses more paper; add a roll if the label says half-drop.

Do I subtract doors and windows?

For wallpaper, usually not: offcuts above and below openings are rarely usable because of the pattern. Only very wide openings like patio doors are worth subtracting.