Wallpaper Calculator
Estimate wallpaper rolls from wall area and roll coverage.
Use decimals when needed. This estimate updates live and is safe to tweak before you buy materials.
Wallpaper Buying Guide
This guide helps you turn your wallpaper calculator result into a cleaner purchase plan. Use it when you want fewer return trips, better waste assumptions, and a more realistic cart.
Step 1: Measure twice
Take two independent measurements and use the larger value when they differ. That single decision prevents most material shortages.
Step 2: Set realistic waste
Simple layouts use lower waste, while angled cuts and pattern matching push waste higher. Do not force one waste value for every room.
Step 3: Buy by package unit
Suppliers sell by boxes, bundles, or rolls. Convert your estimate to purchase units and round up once at checkout.
Cost planning rule of thumb
Build your budget in three bands: material-only, material+consumables, and full project with tool contingency. This keeps expectations realistic before you buy.
Recommended for this job
Commonly paired tools and accessories
These are the practical extras people often forget until the last minute, especially when turning a rough estimate into a real purchase list.
Wallpaper smoothing kitWhy this helps: Common add-on that reduces last-minute store runs once the estimate is final.
Wallpaper adhesiveWhy this helps: Common add-on that reduces last-minute store runs once the estimate is final.
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Wallpaper Calculator FAQ
What is pattern matching and why is it important?
If you buy a wallpaper with a pattern, such as flowers or stripes, the strips (wallpaper lengths) must be matched so that the pattern continues seamlessly from one strip to the next. This means you have to shift the strip up or down until the pattern aligns, which results in a piece of the wallpaper at each end having to be cut off and thrown away. This repetition is called the pattern repeat. The larger the repeat, the more waste there will be. Our calculator automatically takes this into account if you specify the pattern repeat height.
Should I apply the paste to the wall or the wallpaper?
This depends entirely on what type of wallpaper you have bought. The vast majority of modern wallpapers today are so-called 'Non-woven' wallpapers (often called paste-the-wall). For these, you should roll the paste directly onto the wall, which is much easier and less messy. Older paper wallpapers require you to apply the paste to the back of the wallpaper and let it soak for about 5-10 minutes before putting it up. Always read the instructions on the wallpaper roll carefully, as it is crucial to the result!
How do you prepare the wall before wallpapering?
The preparation is 90% of a successful wallpapering job. Even the most expensive and beautiful wallpaper will look terrible if the wall underneath is bumpy. You must first spackle over all joints, nail holes, and irregularities, and then sand the wall smooth. If you have heavily patterned or dark old wallpapers, it may be necessary to prime the wall first to prevent the old pattern from shining through the new, often lighter, wallpaper.