🌸Wallpaper Calculator
Work out how many rolls of wallpaper you need, including pattern repeat.
Your room
You'll need about
9 rolls
24 strips · 3 strips per roll · 317 sq ft of wall
strips
24
strips per roll
3
sq ft
317
🛒 Shopping list
- Wallpaper rolls (20.5 in × 33 ft)9 rolls
- Wallpaper paste / primer2 tubs
Big pattern repeats waste more paper. Buy all rolls with the same batch number so the colour matches.
How it works
Wall area = room perimeter × height, minus 20 sq ft per door and 15 sq ft per window. Strips = wall area ÷ (roll width × wall height). Each strip is the wall height plus 4 in for trimming, rounded up to the pattern repeat. Rolls = strips ÷ strips per roll, plus waste.
Worked example
A 12 × 10 ft room, 8 ft walls, 1 door, 1 window, 20.5 in × 33 ft rolls, no repeat:
- 44 × 8 − 35 = 317 sq ft of wall
- 317 ÷ (1.71 × 8) = 24 strips, 3 strips per roll
- 24 ÷ 3 = 8, plus 10% = 9 rolls
Questions people ask
The distance before the pattern starts again. You'll find it on the roll label.
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Last updated September 28, 2026. These results are friendly estimates to help you plan — always double-check before buying or making big decisions.