Wallpaper Roll Calculator
Estimate how many wallpaper rolls you need to cover a room, accounting for roll size, pattern repeat and trimming waste.
Room units
m
m
m
m
m
m
Includes a ~10% waste and trimming allowance
8
rollsWallpaper used
80.6%
Waste / trim
19.4%
- 1
Wall perimeter
2 × (4 + 3) = 14 - 2
Drops needed
⌈14 ÷ 0.53⌉ = 27Each drop is one full-height strip of wallpaper. - 3
Usable drops per roll
⌊10.05 ÷ (2.4 + 0)⌋ = 4 - 4
Rolls (base)
⌈27 ÷ 4⌉ = 7 - 5
Rolls with 10% margin
⌈7 × 1.1⌉ = 8
How does this calculator work?
Multiply room length plus width by two for the wall perimeter, divide by roll width to get drops, then divide roll length by wall height plus pattern repeat for usable drops per roll. Divide drops by usable drops, round up, and add about 10% for trimming waste to find rolls needed.
Formula
How this is calculated
The calculator first finds the wall perimeter as 2 × (length + width), which is the total horizontal distance you need to cover with vertical wallpaper strips, called drops. Dividing the perimeter by the roll width (standard European rolls are 0.53 m wide) and rounding up gives the total number of drops required. Room length, width, wall height and pattern repeat can be entered in metres or feet; roll width and length are entered in metres because wallpaper is sold in metric sizes.
Each drop must be at least as long as the wall height plus the pattern repeat, because matching a patterned design forces you to discard part of every drop so the print lines up with the strip beside it. Dividing the roll length (typically 10.05 m) by this drop length and rounding down gives how many usable full-height drops you get from one roll. The rolls needed equal the total drops divided by usable drops per roll, rounded up, then multiplied by roughly 1.10 to cover trimming, mistakes and slight pattern shifts.
The model assumes plain rectangular walls and full-height drops, and it does not subtract doors or large windows, so it errs on the generous side. Set the pattern repeat to 0 for plain or random-match papers. If a wall is taller than one roll can cover (no usable drops), no result is returned. Always buy from the same batch to avoid colour variation.
Frequently asked questions
A patterned design must line up between neighbouring strips, so part of every drop is trimmed off to match the repeat. A larger repeat means more waste per drop, fewer usable drops per roll, and therefore more rolls.
No. It assumes solid walls and full-height drops, which keeps a safe margin. With several large openings you may need slightly fewer rolls, but the built-in ~10% allowance covers trimming and errors.
The defaults of 0.53 m wide and 10.05 m long match standard European rolls. Check your specific wallpaper, as widths and lengths vary, and enter the actual figures for an accurate estimate.
Also known as
TG we-Calculate Editorial Team. (2026). Wallpaper Roll Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/wallpaper-roll-calculator
TG we-Calculate Editorial Team. "Wallpaper Roll Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/wallpaper-roll-calculator.
TG we-Calculate Editorial Team, "Wallpaper Roll Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/wallpaper-roll-calculator
@misc{wecalculate_wallpaper_roll_calculator, title = {Wallpaper Roll Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/wallpaper-roll-calculator}}, year = {2026}, note = {TG we-Calculate} }
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