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Wallpaper Calculator

Work out how many rolls of wallpaper a room needs from its size, the number of doors, the roll size and the pattern repeat.

Rules last checked 25 October 2026Every step shown

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m
m
m
m

A standard roll is 0.53 m × 10.05 m; wide rolls are 0.7 m or 1.06 m.

m
cm

Printed on the label; 0 for plain or free-match paper.

Rolls to buy

7

Drops (strips) needed
28
Drops from each roll
4
Length of each drop
2.5 m
Wall area
34.2 m²

You need 7 rolls: 28 drops of 2.5 m, 4 from each roll.

How it's worked out

  1. Around the room2 × (4 + 3.5) m15 m
  2. Drops15 ÷ 0.53 m, rounded up, less 1 for door28
  3. Drop length2.4 m + 10 cm trim2.5 m
  4. Rolls28 drops ÷ 4 a roll, rounded up7
  • Windows aren't deducted, since you still paper above and below them. Buy one extra roll, and check every roll has the same batch number so the colour matches.

How it works

Drops = perimeter ÷ roll width, rounded up · Drops per roll = roll length ÷ drop length, rounded down · Rolls = drops ÷ drops per roll, rounded up

Each drop is the wall height plus 10 cm for trimming, rounded up to whole pattern repeats. Each door saves one drop of standard paper; windows aren't deducted, because you still paper above and below them.

Example

A 4 × 3.5 m room is 15 m around: 29 drops of 0.53 m paper, less one for the door, makes 28. Each drop is 2.5 m, so a 10.05 m roll gives 4 and you need 7 rolls. With a 53 cm repeat, each drop is 2.65 m, a roll gives 3, and you need 10 rolls.

Questions people ask

How many rolls of wallpaper do I need for a 4 × 3.5 m room?

With 2.4 m walls, one door and standard 0.53 × 10.05 m rolls, 7 rolls for plain paper, or 10 with a 53 cm pattern repeat.

What size is a standard roll?

In the UK and Europe, 0.53 m wide and 10.05 m long, about 5.3 m². Wide rolls are 0.7 m or 1.06 m.

How does the pattern repeat change things?

Each drop has to start at the same point in the pattern, so its length is rounded up to whole repeats. That wastes more of each roll.

Should I buy extra?

Yes, one spare roll, and check that every roll has the same batch number so the colour matches.

Formula and rules last checked 25 October 2026Written and tested by the CalculatorDex teamReport a problem