Wallpaper Calculator

Work out how many rolls of wallpaper a room needs, allowing for the pattern repeat, doors and windows.

Wallpaper is bought by the roll and hung in drops, so the useful answer is how many rolls — with the pattern repeat accounted for, because that is what wastes paper.

0 for a plain paper. It is printed on the roll label.

Rolls to buy

  • Drops needed
  • Drops per roll
  • Length per drop
  • Wall area

    How Does It Work?

    1. Measure the roomLength and width for a whole room, or switch to a single wall for a feature wall. The perimeter is what matters, not the floor area.
    2. Enter the pattern repeatPrinted on the roll label. Zero for a plain paper. This is the number that decides how much you waste, because every drop must start at the same point in the pattern.
    3. Read the rollsThe calculator shows how many drops the room needs, how many drops each roll yields, and therefore how many rolls to buy.

    What Is It Used For?

    Wallpaper is not sold by area, so a figure in square metres is no help at the till. It is hung in vertical drops the width of the roll, and each drop has to be cut to the same length. With a patterned paper every drop must begin at the same point in the design, so the cut length rounds up to a whole number of pattern repeats — a 64 cm repeat on a 2.4 m wall means cutting 2.56 m and discarding the rest. That is why a large repeat can cost you a whole extra roll on the same room.

    • Ordering wallpaper for a bedroom, living room or hallway.
    • Working out a single feature wall without paying for a whole room.
    • Comparing a plain paper against a large-repeat pattern before choosing.
    • Checking a decorator’s estimate before agreeing to it.
    • Deciding how many spare rolls to keep from the same batch.

    Examples

    RoomHeightRepeatRolls
    4 × 4 m (16 m perimeter)2.4 mNone8
    4 × 4 m (16 m perimeter)2.4 m64 cm11
    3 × 4 m (14 m perimeter)2.4 mNone7
    4 m feature wall2.4 mNone2

    Frequently Asked Questions

    How many rolls of wallpaper do I need?

    Divide the perimeter by the roll width to get the number of drops, divide the roll length by the cut length of one drop to get drops per roll, then divide one by the other and round up. For a 16 m perimeter at 2.4 m high with plain paper, that is 31 drops at 4 per roll, so 8 rolls.

    What is a standard roll of wallpaper?

    The common European roll is 10.05 m long and 53 cm wide, covering about 5.3 m² before waste. American rolls are usually wider and shorter. Both boxes are editable, so use whatever your roll label says.

    Why does the pattern repeat need more rolls?

    Every drop has to start at the same point in the design, so each cut length rounds up to a whole number of repeats. A 2.4 m wall with a 64 cm repeat needs 2.56 m per drop, and that extra 16 cm per drop is waste. Large repeats can add a roll or two to the same room.

    Should I deduct doors and windows?

    Only roughly. Trade practice is to deduct about one drop width per average opening, which is what the options here do. Deducting the exact area is a mistake, because the offcuts above and below an opening rarely fit anywhere useful.

    How much extra should I order?

    The calculator already rounds up to whole rolls, which usually leaves a sensible margin. Buy any spare roll at the same time and from the same batch — shades differ between production runs, and a mismatched repair is very visible.

    Free. No registration. This tool runs entirely in your browser, so the data you enter stays on your device.