Wallpaper Calculator
Estimate how many wallpaper rolls you need, accounting for wall size, roll dimensions and pattern repeat.
Result
Enter your numbers to see the estimate.
How this calculator works
Wallpaper is one of the trickier materials to estimate because rolls come in different widths and lengths depending on the manufacturer, and patterned wallpaper needs extra length per strip to match the design at each seam — called the pattern repeat.
This calculator works out how many vertical strips fit across your total wall width, how many strips one roll can produce given your wall height plus pattern repeat allowance, and from there, how many rolls you need in total. Plain or textured wallpaper with no repeat is the most efficient — nearly the full roll length is usable for strips.
Always buy your wallpaper in a single batch from the same dye lot when possible, since color can vary slightly between production runs. Buying one extra roll beyond the calculated amount is a common recommendation to cover mistakes, awkward corners around windows and doors, and future repairs.
Example: Four walls totalling 40 linear ft, each 8 ft high, using rolls that are 20.5 in wide × 33 ft long with no pattern repeat, need about 6-7 rolls.
How it works
Enter your measurements or costs
Fill in the room size, materials or costs for your project. No sign-up required.
Adjust the settings
Choose your units, waste percentage and any project-specific options.
Get your estimate instantly
See your results calculated instantly, right in your browser.
Frequently asked questions
How many rolls of wallpaper do I need?
It depends on your wall dimensions, roll size and pattern repeat. This calculator works out strips per roll and total strips needed to give you a roll count.
What is pattern repeat and why does it matter?
Pattern repeat is the vertical distance before a wallpaper's design repeats. Patterned wallpaper needs extra length per strip so the pattern lines up at the seams, which uses more roll per strip than plain wallpaper.
Should I buy extra wallpaper rolls?
Yes, buying one extra roll beyond your calculated total is standard practice, to cover mistakes, awkward cuts around outlets and windows, and future repairs from the same dye lot.
Does wallpaper come in standard sizes?
Roll sizes vary by manufacturer and country. US rolls are commonly around 20.5 in wide; European rolls are often 21 in (53 cm) wide. Always check your specific product's roll width and length.
Can I use these calculators on my phone?
Yes, every HomeCalc calculator is mobile-friendly and works on any device with a browser.