DIY & materials
Wallpaper Roll Calculator
Calculate full drops, repeat matching and roll quantities. This free wallpaper roll calculator shows the calculation and its assumptions so you can compare your own figures.
Your results
Calculate full drops, repeat matching and roll quantities.
Calculated outcomes
- Perimeter M
- 18
- Net Wall Area M2
- 39.2 m²
- Matched Drop M
- 2.5
- Drops Per Roll
- 4
- Area Only Minimum Rolls
- 8
Assumptions and estimates
- Recommended rolls use full-height strips, trim allowance and straight-match repeat. Window/door area deductions affect only the theoretical area minimum; they rarely save full drops. Only enter verified full-height opening widths in the perimeter deduction. Offset/half-drop matching needs supplier-specific allowances.
- Method: Round each full drop to the pattern repeat, calculate drops per roll, then round required rolls upward.
- Small windows and doors reduce area but often do not remove full drops. The strip-based order estimate therefore avoids subtracting their area from roll counts.
Useful next steps
- Use Compare options to test an alternative side by side.
- Copy, print or download a record of this calculation when you need one.
Reports open your email app addressed to s@s1.ie with the public page address only. Your inputs are never added.
How the wallpaper rolls calculation works
Round each full drop to the pattern repeat, calculate drops per roll, then round required rolls upward.
Small windows and doors reduce area but often do not remove full drops. The strip-based order estimate therefore avoids subtracting their area from roll counts.
Using this calculator
- Enter your own figures in the labelled inputs. Keep the currencies, units and time periods consistent.
- Choose any applicable rate profile, pattern or assumption shown for this tool. Open additional inputs when relevant.
- Review recommended rolls and drops required, then read the stated assumptions and eligibility conditions before using the result.
Worked example
This is a static example using illustrative inputs, not facts about you or today’s date. The displayed eligibility selections and assumptions apply only to this example.
See example inputs
- Room length (m)
- 5
- Room width (m)
- 4
- Wall height (m)
- 2.4
- Window / door area (m²)
- 4
- Full-height uncovered wall width (m)
- 0
- Pattern repeat (cm)
- 0
- Trimming allowance per drop (cm)
- 10
- Roll width (cm)
- 53
- Roll length (m)
- 10
- Recommended Rolls
- 9
- Drops Required
- 34