Home & DIY calculator
Plan full-height wallpaper strips, repeat matching and whole rolls.
With 2.5 m walls and 10 cm trim, each strip is cut at 2.6 m, so a 10 m roll gives 3 full strips. An 18 m perimeter needs 18 ÷ 0.53 = 33.96, rounded up to 34 strips, plus one spare: 35 strips, or 12 rolls.
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Use the same wall height for this run; calculate different heights separately.
With 2.5 m walls and 10 cm trim, each strip is cut at 2.6 m, so a 10 m roll gives 3 full strips. An 18 m perimeter needs 18 ÷ 0.53 = 33.96, rounded up to 34 strips, plus one spare: 35 strips, or 12 rolls.
| Input | Value |
|---|---|
| Wall run | 18 m |
| Wall height | 2.5 m |
| Roll width | 0.53 m |
| Roll length | 10 m |
| Pattern repeat | 0 cm |
| Trim per strip | 10 cm |
| Spare strips | 1 |
| Result | Value |
|---|---|
| Cut length per strip | 2.6 m |
| Strips required | 35 |
| Full strips per roll | 3 |
| Rolls to buy | 12 |
| Remainder per roll | 2.2 m |
Matching a pattern can discard part of each cut length. The calculation rounds the required drop to the repeat before counting usable drops per roll. Enter the roll's actual dimensions and match information; comparing wall area with roll area misses those cutting losses.
Only if its size, pattern position and orientation fit that location. The conservative layout does not assume perfect reuse of all scraps. Check the hanging plan before reducing the order, and keep rolls from one production batch where the manufacturer recommends it.
The wall height, trimming allowance and pattern repeat control the length of each wallpaper drop. The wall width controls how many drops are needed at the selected roll width. Measure each wall and use the actual product dimensions; floor area alone cannot establish the number of wallpaper rolls to buy.
Calculation/content reviewed 4 October 2026. Source: Babushka Market’s displayed formulas, units and labelled editable assumptions. How the estimates work
