Free Wallpaper Calculator

Calculate exactly how many rolls you need. Accounts for pattern repeat, waste factor, doors, and windows. Multiple rooms supported.

Wallpaper Roll Size

Walls

Wall 1
Wall 2
Wall 3
Wall 4

Enter wall dimensions

Results appear automatically

How we calculate

1

Count panels per wall

Wall width ÷ roll width = strips needed. Calculated independently for each wall in each room.

2

Account for pattern repeat

Each panel cut rounds up to the next repeat. Fewer panels fit per roll = more rolls needed.

3

Sum per room

Panels ÷ panels-per-roll per wall, summed per room. More accurate than simple area ÷ coverage.

Frequently Asked Questions

How many rolls of wallpaper do I need for a room?

It depends on wall dimensions, roll size, and pattern repeat. Our calculator uses the panel method — counting exact strips needed per wall — which is more accurate than simply dividing area by roll coverage.

Can I calculate multiple rooms at once?

Yes! Click '+ Add Room' to add as many rooms as you need. Each room calculates independently, and you get a combined total at the top.

What is pattern repeat and why does it matter?

Pattern repeat is the vertical distance between identical points in the wallpaper design. A 25-inch repeat means each panel must be cut at multiples of 25 inches, creating waste. A higher repeat means fewer panels per roll and more rolls needed.

How much waste factor should I add?

Standard practice is 10% for most installations. For complex rooms with many corners, angles, or obstacles, use 15%. For simple rectangular rooms with no pattern, you can use 5% or even 0%.

What size is a standard wallpaper roll?

In the US, standard single rolls are 20.5" wide x 33ft long (~56 sq ft). European rolls are typically 20.5" x 27ft (~46 sq ft). Wide rolls are 27" wide and come in various lengths (15ft, 27ft, 30ft).

Is this calculator accurate for grasscloth and specialty wallpapers?

Yes. As long as you enter the correct roll width, length, and pattern repeat, the panel-based calculation works for all wallpaper types including grasscloth, vinyl, fabric, and murals.

Built by wallpaper installers, for wallpaper installers.

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