Free wallpaper roll calculator with pattern repeat support. Enter total wall width, height, roll size, and pattern repeat to get the exact number of rolls needed, including door/window deductions and a waste buffer.
Use before ordering wallpaper for a full room, especially with a bold pattern that has a visible repeat — it prevents an expensive mid-job reorder from a different dye lot.
Many wallpaper calculators ignore pattern repeat entirely, quietly underestimating rolls for patterned designs. This one bakes the repeat into the drop math.
If a pattern repeat is set, each drop is rounded up to the next full repeat length; otherwise the drop equals the wall height exactly.
Drops per roll = roll length ÷ effective drop length, and strips needed = total wall width ÷ roll width, minus any strips saved by large door/window openings.
Rolls needed = (net strips ÷ drops per roll), inflated by your waste buffer percentage and rounded up to a whole roll.
A pattern repeat forces every drop to start at the same point in the design, so each cut strip must be rounded up to the next full repeat length rather than the exact wall height. That shortens how many usable drops you get from each roll, which is why large repeats can noticeably increase the total rolls needed.
Wallpaper color and pattern alignment can shift subtly between production runs, even for the identical SKU. Buying every roll for a room from a single batch avoids visible seams or color banding where a later-purchased roll meets an earlier one.
Add up the width of every wall you're covering, in a continuous loop around the room, without subtracting for corners — corners just mean a strip gets split across two walls, not removed. Enter door and window openings separately in the deduction field instead of subtracting them from the wall width directly.
입력
480" total wall width, 96" wall height, 20.5" roll width, 33 ft roll length, 0" pattern repeat, 0 sq ft deducted, 10% waste.
출력
7 rolls needed.
Effective drop = 96" (no repeat). Drops per roll = floor(396/96) = 4. Strips needed = ceil(480/20.5) = 24. Rolls = ceil((24/4) × 1.10) = ceil(6.6) = 7.