Wallpaper Calculator
Free wallpaper calculator to estimate rolls from wall area, roll coverage, and waste.
Results
15Rolls to buy
- 14.67Exact rolls
How it works
Rolls = (wall area × (1 + waste%)) ÷ roll coverage. We ceil to whole rolls.
Worked example
Example: 320 sq ft walls, 30 sq ft/roll, 15% waste → about 13 rolls to buy.
Measure walls carefully
Add up height × width for each wall to cover. Subtract large openings. Pattern repeats may increase waste beyond a simple area ratio.
Roll coverage
US rolls often cover about 25–30 sq ft; metrics rolls vary. Always use the coverage printed on your product, not a generic average.
Pattern matching
Large repeats can push waste to 15–20%. Order from one dye lot and keep a spare roll for repairs.
Frequently asked questions
How many rolls of wallpaper do I need?
Divide adjusted wall area by the roll’s coverage, then add waste for cuts and matching. This calculator does that math for you.
What waste percent for patterned paper?
Start around 15% for moderate repeats. Bold murals or large matches may need more—ask the manufacturer.
Can I mix American and European roll sizes?
Avoid mixing. Enter the exact coverage for the rolls you will buy.
Estimates only. Verify coverage rates and local requirements before purchasing materials. Not a substitute for professional advice.