About the wallpaper calculator
Wallpaper is hung in vertical strips called drops. The number of rolls depends on how many drops you need and how many full drops each roll yields after allowing for the pattern repeat.
How to use this calculator
- Enter the room perimeter and wall height.
- Enter the roll width and length from the label.
- Add any pattern repeat and openings.
Worked examples
- 48 ÷ 1.708 = 28.1 → 29 drops
- 33 ÷ 8 = 4 drops per roll
- 29 ÷ 4 × 1.1 = 7.98 → 8 rolls
8 rolls.
Measurement guidance
Pattern repeat
The repeat is printed on the label. Drop-match patterns can waste more; add extra allowance for large repeats.
Frequently asked questions
Should I subtract doors and windows?
Only large openings — small ones rarely save a full drop.
Why buy from one lot?
Colors can vary slightly between print runs.