Wallpaper Calculator
Rolls of wallpaper needed, allowing for the pattern repeat.
About this calculator
Wallpaper is the trickiest material to estimate because of the pattern repeat: every drop must start at the same point in the pattern, so tall repeats waste paper on every length. This calculator works in drops — how many lengths you need, how many usable lengths each roll yields — which is how decorators actually count.
The formula
Worked example
10m of wall, 2.4m high, 32cm repeat: drop = 2.56m → 3 drops/roll; 19 drops needed → 7 rolls. Plain paper would need 6.
Common mistakes
- Ignoring the pattern repeat — the single biggest cause of running short.
- Buying rolls from different batches, which vary visibly in shade.
- Not adding trim allowance for the top and bottom cut.
Frequently asked questions
Assumptions & limitations
Standard 10.05m × 53cm rolls. Non-standard widths change the answer — adjust with the roll label figures.
Sources & verification
- Manufacturer roll dimensions — UK standard rolls are 10.05 m × 0.53 m; pattern repeat reduces usable length — both are printed on the roll label
All sources last accessed 24 July 2026.
Spotted an error or an out-of-date figure? Report it — corrections are prioritised over all other work (see our corrections policy).