Wallpaper Calculator
How many rolls of wallpaper a room takes, counted strip by strip.
Good to know. Buy every roll from the same batch. Two batches of the same paper can be a shade apart.
Approximate. Real-world values vary.
How it works
In plain words
Divide the total width of the walls by the roll width to get the number of strips. Each strip is the wall height plus 10 cm (4 in) for trimming, rounded up to a whole pattern repeat. Divide the roll length by the strip length and round down to get whole strips per roll. Rolls = strips ÷ strips per roll, rounded up.
The formula
strips = walls ÷ roll width, rounded up strip = height + trim, rounded up to the repeat per roll = roll length ÷ strip, rounded down rolls = strips ÷ per roll, rounded up
Worked example
14 m of wall 2.5 m high takes 27 strips of 53 cm. A 10.05 m roll gives 3 strips of 2.6 m, so you need 9 rolls.
Sources
- Manufacturers’ standard roll sizes 0.53 × 10.05 m in the UK and Europe; US double rolls of about 20.5 in × 33 ft.
Sources checked September 29, 2026. 6 automated tests check its answers on every change.
About the wallpaper calculator
Wallpaper is not bought by the square metre, because it is hung in strips from ceiling to floor and the offcut at the end of each roll is usually too short to use. So the calculator counts strips: how many fit around the room, and how many whole strips each roll gives.
Measure the width of every wall you are papering and add them up. For most rooms, don’t take off doors and windows: the strips above and below them still need paper and cutting around frames wastes some. Take off only large openings, such as patio doors or a wide archway.
Patterned paper needs more. Each strip has to start at the same point in the pattern, so its length is rounded up to a whole number of repeats, and a large repeat can cost one strip per roll. The repeat is printed on the label, often as a symbol with a number of centimetres or inches.
Standard rolls in the UK and Europe are 53 cm wide and 10.05 m long. In the US, wallpaper is priced by the single roll but sold in double rolls, commonly 20.5 in by 33 ft. Wide papers exist too; choose another size and enter it from the label.
Questions people ask
How many rolls of wallpaper do I need for a room?
For a 4 × 3 m room with 2.5 m walls (14 m of wall), 9 standard rolls of 53 cm × 10.05 m, with a plain paper.
Should I subtract doors and windows?
Usually not. The paper above and below them and the cutting around frames use most of what you would save. Subtract only very large openings.
How does the pattern repeat change the number of rolls?
Each strip is rounded up to a whole repeat so the pattern lines up, which can mean fewer strips per roll and more rolls. A 64 cm repeat on 2.5 m walls makes each strip 3.2 m, so a roll gives 3 strips.
What size is a US wallpaper roll?
Wallpaper in the US is usually sold in double rolls of about 20.5 in by 33 ft, around 56 square feet, even when priced per single roll.