Wallpaper Calculator

Estimate rolls of wallpaper for a room, with waste for matching.

Wall area

Coverage per roll

Waste (%)

Price per roll ($)

Rolls needed (rolls) 17

Total cost ($) 0

Formula: rolls = wall area × (1 + waste) ÷ coverage per roll

Step-by-step with your numbers:

1. Values used:

2. Wall area = 400

3. Coverage per roll = 28

4. Waste = 15 %

5. Price per roll = 0 $

7. Rolls needed = 17rolls

8. Total cost = 0$

Did we solve your problem today?

Find how many rolls of wallpaper you need. Extra waste is added because pattern repeats mean parts of each roll are trimmed off.

The math behind it

Rolls = wall area × (1 + waste) ÷ usable coverage per roll, rounded up.

A standard US double roll covers ~56 ft² (single ~28 ft²); patterned papers need more waste.

400 ft² of wall, 28 ft²/roll, 15% waste → 400 × 1.15 ÷ 28 = 17 rolls.

Why so much waste?

Pattern repeats must align between strips, so the top of each strip is often cut off and discarded.