Wallpaper calculator
Easily calculate how much wallpaper you need.
With our wallpaper calculator, you know within seconds how many rolls of wallpaper you need for your wall. You will find it on every wallpaper product page: enter the width and height of your wall in centimeters, and the result appears right away. The calculator uses the actual roll size and pattern repeat of that wallpaper, and takes into account:
- a trim allowance of 5 cm per strip;
- the pattern repeat, so every strip lines up with the pattern;
- half drop (offset pattern), where applicable.
How to calculate how many rolls of wallpaper you need
Want to check the numbers yourself? This is how our calculator works for a roll with a straight pattern match:
- Number of strips = (wall width + 5 cm) ÷ roll width, rounded up.
- Length per strip = wall height + 5 cm, rounded up to a whole number of pattern repeats.
- Strips per roll = roll length ÷ length per strip, rounded down.
- Number of rolls = number of strips ÷ strips per roll, rounded up.
Example. A wall 400 cm wide and 240 cm high, with wallpaper 53 cm wide and 10.05 m per roll. You need 8 strips (405 ÷ 53 = 7.6). Without a pattern, each strip is 245 cm, so you get 4 strips from a roll and need 2 rolls. If the wallpaper has a pattern repeat of 64 cm, each strip becomes 256 cm (4 × 64). You then get only 3 strips from a roll and need 3 rolls. So the repeat often makes the difference.
Please note: the calculator does not subtract windows, doors or sloping walls. The result is an indication only and is not binding.
Tip from our specialists
Not sure about the calculation or the direction of the pattern? Email us your wall measurements and we will check the numbers for you.
How many rolls of wallpaper do I need?
That depends on your wall measurements, the roll size and the pattern repeat. Work out the number of strips (wall width + 5 cm, divided by the roll width), determine how many strips you get from one roll (roll length divided by the strip length including the repeat) and divide the number of strips by the strips per roll. On the product page, our calculator does this automatically with the actual dimensions of that wallpaper.
What is a pattern repeat and why does it mean I need more wallpaper?
The repeat is the height after which the pattern repeats itself. Each strip has to line up with the pattern of the previous one, so you round the strip length up to a whole number of repeats. With a large repeat, more is left over per strip and you get fewer strips from a roll.
What does half drop (offset pattern) mean?
With a half drop, the pattern shifts by half a repeat from one strip to the next. As a result, every other strip is longer and you often need a little more wallpaper. Our calculator takes this into account automatically when the wallpaper has a half drop.
Should I subtract windows and doors?
For small windows and doors, preferably not: a lot is lost to cutting around the frames. The calculator deliberately does not subtract them. For a large glass wall or an open doorway, you can subtract that width from the wall width.
Should I order an extra roll?
With a large repeat or a lot of cutting, an extra roll is a sensible choice. Wallpaper is made in production batches, and a later batch can differ slightly in color. So order everything at once, and keep a leftover roll for repairs later on.
How do I calculate made-to-measure wallpaper, murals or panels?
Made-to-measure wallpaper and murals are ordered per m² or as panels sized to your wall. Measure the width and height of your wall from baseboard to ceiling, without a margin, and enter those measurements on the product page: the calculator then works out the m² or the number of panels. Not sure? Email us your measurements.
Measuring in inches?
On our US site, the wallpaper calculator on every product page works in inches by default. Wondering how European rolls compare to American double rolls? Our guide translates roll sizes into inches and square feet: European Rolls vs. Double Rolls: Sizes in Inches.
