How this calculator works
We take the wall area, subtract the openings, add an allowance for the pattern (a larger repeat wastes more paper when you match the strips), and divide by how much paper one roll covers once the trimmed ends are accounted for.
Worked example: four 10 ft walls that are 8 ft tall have 320 ft². With 40 ft² of doors and windows removed, 280 ft² remain. For a small repeat (15% allowance) that is 322 ft², which is 12 single rolls at 28 ft² each.
Tips before you buy
- Wallpaper is returned rarely, and the dye lot may not match later, so buy one extra roll for repairs and mistakes.
- For high-priced paper, count strips instead of area. Divide the wall width by the roll width to get the number of drops, then see how many drops you can cut from one roll after allowing for the pattern repeat.
- Check the pattern repeat on the label. It decides how much paper each strip wastes.
Tools & materials for this project
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Frequently asked questions
How many rolls of wallpaper do I need for a room?
Divide the wall area (minus openings, plus waste) by the usable coverage of a roll. A 10 × 10 ft room with 8 ft walls typically takes 10 to 13 single rolls.
How much wallpaper should I add for pattern match?
10 to 25%, depending on the repeat. Plain or random patterns need the least, and big drop-match patterns the most.
What is the difference between a single and a double roll?
A double roll is simply two single rolls wound together, so it covers about twice as much: roughly 56 ft² against 28 ft² usable.
Related calculators & guides
Estimates only. Results assume standard materials and simple shapes. Supplier products vary, and the final call on quantity, structure and safety is yours. Check your local code and your supplier's guidance before ordering.