Wallpaper Calculator
Find how many rolls of wallpaper a room needs from its size, doors, windows, and the coverage of one roll.
Roll coverage varies by brand; 56 sq ft is typical for a standard double roll. Large pattern repeats waste more, so add a roll for bold designs.
Enter the room size to find the rolls of wallpaper.
How to use the wallpaper calculator
Enter the room length, width, and wall height, then how many doors and windows to leave out. Set the coverage of one roll, printed on the label, and the calculator returns the rolls to buy, rounded up to whole rolls.
The wall area is the perimeter times the height, so it works for any rectangular room. For a feature wall rather than the whole room, treat that single wall as the space and enter its width and height directly.
Roll coverage varies by brand
Wallpaper rolls are not a single standard size. A standard American double roll covers roughly 56 square feet of usable area, which is the default here, while European rolls and designer brands differ. Always check the figure on the roll you have chosen.
The usable area is less than the raw roll size, because the top and bottom of each strip is trimmed and some length is lost lining strips up. The coverage figure on the label already accounts for normal trimming, so enter that number rather than the raw roll length.
Pattern repeat changes the math
A plain or small-pattern paper uses almost the whole roll. A large pattern repeat wastes more, because each new strip has to start at the same point in the design to line up with its neighbor, and the offcut at the top is often discarded.
The bigger the repeat, the more you lose per strip. For a bold, large-scale pattern, buy an extra roll or two beyond the calculated figure, and check the repeat length on the label so you know how much to add.
Order from the same batch
Wallpaper is printed in batches, and the color can shift slightly between print runs. Rolls from one batch carry the same batch or lot number, so buying enough at once avoids a visible mismatch halfway across a wall.
Because a part roll still means buying a whole one, and because a repeat job risks a different batch, it pays to round up generously. A spare roll also covers a future repair without a hunt for the exact paper.
Frequently asked questions
- How many rolls of wallpaper do I need?
- Work out the wall area as the room perimeter times the height, subtract doors and windows, and divide by the coverage of one roll. The calculator does this and rounds up, since rolls are sold whole.
- How much does one roll of wallpaper cover?
- A standard American double roll covers about 56 square feet of usable area, the default here. Coverage varies by brand and region, so check the figure on your chosen roll and enter it.
- Why does a large pattern need more wallpaper?
- Each strip must start at the same point in the design to line up with the last, so the offcut at the top of every strip is wasted. The bigger the repeat, the more you lose, so add extra rolls for bold patterns.
- Should I buy all the wallpaper at once?
- Yes. Color can shift between print batches, so buy enough from one batch number to finish the job and keep a spare. A later top-up order may not match the original exactly.
- Can I paper just one feature wall?
- Yes. Enter that wall's width and height in place of the room dimensions and set doors and windows to zero if the wall is solid. The result is the rolls for that single wall.