Calculating how much wallpaper you need is one of the most important steps in any wallpaper project. Order too little and you'll face delays waiting for more stock — and dye lots can vary between print runs, meaning new rolls may not match perfectly. Order too much and you've wasted money. This guide walks you through exactly how to calculate the right amount of peel and stick wallpaper for any room or accent wall, including how to account for pattern repeats and waste.
The Basic Formula: How to Calculate Wallpaper Quantity
The basic calculation for wallpaper quantity is straightforward:
- Measure the width of your wall in metres or feet.
- Measure the height of your wall from floor to ceiling (or from where you want the wallpaper to start to where you want it to end).
- Calculate the wall area: Width × Height = Total square metres (or square feet).
- Add 10-15% for waste and trimming: Multiply your total area by 1.10 to 1.15.
- Divide by the coverage per roll to find the number of rolls needed.
Each roll of Peel & Pattern wallpaper covers a specific area — check the product listing for the exact coverage per roll.
How to Account for Pattern Repeats
If your chosen wallpaper has a pattern repeat, you'll need to order extra to account for pattern matching between strips. The larger the pattern repeat, the more waste you'll have.
To calculate extra for pattern repeats:
- Note the pattern repeat length from the product listing.
- For each strip, add one full pattern repeat length to the strip height to ensure you have enough to align the pattern.
- Recalculate your total area using this adjusted strip height.
As a general rule, add an extra 15-20% for wallpaper with a large pattern repeat (over 30cm / 12 inches). For wallpaper with no pattern repeat or a small repeat, 10% extra is sufficient.
Calculating Wallpaper for an Accent Wall
For a single accent wall, the calculation is simple:
- Measure the width and height of the wall.
- Subtract the area of any large windows or doors (optional — many people skip this step and use the offcuts for repairs).
- Multiply width × height to get the total area.
- Add 10-15% for waste.
- Divide by the coverage per roll.
Calculating Wallpaper for a Full Room
For a full room installation:
- Measure the width of each wall and add them together to get the total perimeter.
- Multiply the total perimeter by the ceiling height to get the total wall area.
- Subtract the area of doors and windows (each standard door is approximately 2m² / 21 sq ft; each standard window is approximately 1.5m² / 16 sq ft).
- Add 10-15% for waste (or 15-20% for large pattern repeats).
- Divide by the coverage per roll.
Wallpaper Quantity Quick Reference
As a rough guide for standard ceiling heights (2.4m / 8ft):
- Small accent wall (up to 3m / 10ft wide): 2-3 rolls
- Standard accent wall (3-4m / 10-13ft wide): 3-4 rolls
- Small room (bathroom, powder room): 4-6 rolls
- Medium room (bedroom, home office): 8-12 rolls
- Large room (living room, dining room): 12-16 rolls
These are estimates only — always calculate based on your specific wall measurements.
Our Recommendation: Always Order Extra
We always recommend ordering at least 10% more wallpaper than your calculation suggests. Wallpaper is printed in batches, and dye lots can vary slightly between print runs. Having extra from the same batch means you can make repairs or adjustments without worrying about color matching. Unused rolls can be kept for future repairs.
Need Help Calculating?
If you're unsure how much wallpaper to order, contact us at Peel & Pattern and we'll help you calculate the right quantity for your specific project. Browse our full collection and find your perfect pattern — then get in touch with your wall measurements and we'll do the math.