Wallpaper Calculator
Estimate how many rolls of wallpaper a room needs from its perimeter and height — with deductions for doors and windows and extra waste for a pattern repeat, so you buy enough matching rolls without overspending.
How to Use
- Enter the room perimeter in feet — add up the length of every wall you are papering.
- Enter the ceiling height in feet to set the strip length.
- Enter how many doors and windows are in the room so their area is deducted.
- Pick the roll coverage that matches your wallpaper (US single, US double, or European).
- Enter the pattern repeat in inches if the paper has one, then read the rolls needed below.
Show Work
Notes
About the Wallpaper Calculator
The Wallpaper Calculator is a simple, free helper for building, materials estimation and site work that runs entirely on your own device. Estimate how many rolls of wallpaper a room needs from its perimeter and height — with deductions for doors and windows and extra waste for a pattern repeat, so you buy enough matching rolls without overspending.
How it works
Enter your figures and the result appears instantly, updating the moment you change anything. There is no submit button and nothing to wait for, so it is easy to try a few what-if numbers and compare the results. Just check each box holds the kind of value it expects.
Want the deeper story? The Knowledge Base explains the ideas behind the tools in more detail.
Frequently Asked Questions
How does the pattern repeat affect how much I need?
A pattern repeat means each strip has to be cut so the design lines up with the strip beside it, and the off-cut at the top or bottom is scrap. The larger the repeat, the more you waste — a big repeat can add 15% or more. Enter the repeat from the roll label so the estimate accounts for that matching waste.
What is the difference between single and double rolls?
Wallpaper is priced and packaged in single rolls but almost always sold as double rolls, which are one continuous bolt of two singles. A double roll has less waste because you get more full-length strips out of one bolt. Match the dropdown to how your paper is sold — a US single covers about 56 ft² but yields less usable area after trimming.
Should I subtract doors and windows?
Deduct them, but conservatively. Each opening is roughly 15 to 21 ft² of wall you will not cover, and this tool subtracts an allowance per door and window. Do not over-deduct, though — you still cut around openings and want full strips, so it is better to land slightly long than to run out mid-wall.
Why should I always round up and buy extra?
You cannot buy a partial roll, and a single short strip means another order — likely from a different print run that does not match. Always round up to whole rolls and keep at least one spare. The leftover is your repair stock if a strip is damaged or a corner peels down the road.
Do I measure the perimeter including closets and nooks?
Measure the perimeter of every wall surface you intend to paper, including the returns into a nook or the faces of a chimney breast, since each adds strips. Skip closet interiors unless you are papering them. Measuring the true perimeter rather than just the room's nominal size keeps the roll count honest.
How do I use the Wallpaper Calculator?
Just type your numbers. The answer shows up right away — there is no button to press. Change anything and it updates by itself.
Does it cost anything or need an account?
No. The tool is completely free, there is no account to create, and it keeps working offline after the page first loads.
Is anything I type uploaded?
No. The tool works entirely on your device, so the values you enter never leave your browser.
Common Use Cases
Papering a full room
Turn perimeter and height into a roll count with door and window deductions built in.
Doing an accent wall
Estimate rolls for a single feature wall without over-buying for the whole room.
Budgeting a patterned paper
Add the pattern repeat so the estimate reflects the real matching waste before you price it.
Matching roll formats
Switch between US single, US double, and European rolls to match exactly how your paper is sold.
Ordering with spare stock
Round up to whole rolls and keep a spare from the same batch for future repairs.
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