Wallpaper Calculator – Simple, Accurate Roll Estimates
This wallpaper calculator helps you quickly work out how many wallpaper rolls you need for a room. Enter your room’s length, width, and wall height; we calculate the wall area (2 × (L + W) × H), subtract standard door and window areas, and factor in pattern repeat to determine how many full-height strips you’ll get from each roll. It supports both metric and imperial units and common roll sizes.
How the Calculator Works
We use a strip-based method for accuracy. The effective strip length is your wall height rounded up to the next pattern repeat,
so patterned designs get the extra allowance they need. Strips per roll = floor(roll_length ÷ effective_strip_length).
Coverage per roll = strips_per_roll × roll_width × wall_height (we count usable wall area, not waste).
Total rolls = ceil(net_wall_area ÷ coverage_per_roll).
Practical Tips
- Buy an extra roll if possible. Shade/batch numbers can vary; a spare ensures perfect future touch-ups.
- For bold patterns, a larger pattern repeat means more waste per strip—check the label before purchasing.
- Let rolls acclimate and follow the manufacturer’s paste-the-wall or paste-the-paper instructions.
- Store unused rolls flat and dry; label them with the room and date.
Related Calculators
- Paint Calculator – planning a base coat or painting adjoining rooms?
- Tile Calculator – useful for bathrooms or kitchen renovations.
Important Estimate Disclaimer
The results provided by this calculator are intended as general estimates only and should not be considered precise engineering measurements. Actual material requirements, costs, and quantities can vary significantly based on site conditions, local building codes, soil type, reinforcement requirements, climate exposure, and the intended use of your project.
These calculators are designed to help you plan and budget your project more effectively, but they do not replace professional advice from a qualified contractor, engineer, or building inspector. Always verify your calculations and assumptions with trained professionals before placing material orders or commencing construction.
For more information on the assumptions, formulas, and data used in these tools, see our Data Sources and Methodology pages.
Material estimates, cost figures, and volume calculations are approximate and may not reflect your actual requirements. Always double-check dimensions and project-specific needs, and consider adding a contingency allowance for waste, over-excavation, and unforeseen conditions.
If you are unsure about any aspect of your project — including structural requirements, reinforcement needs, drainage, or load-bearing capacity — consult with a licensed professional before proceeding.