Wallpaper Calculator

How many rolls you need — pattern matching included.

How to use this calculator

Enter room dimensions and door/window areas, then press Calculate. Wall area and double rolls needed are shown.

Worked example

Take a 12 ft by 10 ft room with 8 ft walls. The perimeter is (12+10) x 2 = 44 ft, so the wall area is 44 x 8 = 352 square feet. Subtract a 21 sq ft door and a 15 sq ft window to get about 316 sq ft of wallpaperable wall. Most single rolls cover roughly 25-30 sq ft, so you need about 11-12 rolls depending on pattern match.

Why the door and window fields matter

Every door and window you subtract saves real money - wallpaper is priced per roll and per pattern. Counting them also prevents the reverse mistake: ordering too little and running out mid-wall, which forces a partial reorder that may not match the dye lot.

Add extra for pattern matching

Patterned paper needs a "match" allowance because each strip must line up with the next, wasting several inches per drop. Budget 10-15% extra for patterns and only 5% for plain or solid paper.

Frequently asked questions

Does wallpaper come in double rolls?

Yes - many brands sell double rolls that are just two single rolls on one spool. Check the label's square footage, not the roll count, when ordering.

Wallpaper is sold by the roll, but coverage varies by brand, so always confirm the square footage printed on the label you plan to buy. When in doubt between two sizes, order the larger - unopened rolls are usually returnable and a partial reorder may not match color.