DIY Cost Tools
Wallpaper Calculator
Estimate wallpaper strips, usable strips per roll, whole rolls, waste, and material cost while accounting for wall height and pattern repeat.
Measure: Measure the room perimeter and wall height, subtract major openings, and copy the exact roll width, roll length, and pattern repeat from the label.
How the estimate works: The calculator uses your measurements, unit conversions, waste allowance, and product coverage to create a planning quantity. Review the formula shown above, then read the matching guide below before ordering. See How Our Calculators Work for assumptions and limitations.
Recommended wallpaper tools and supplies
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These practical options match the work estimated by this calculator. Verify compatibility, specifications, and the current price before purchasing.
Check that adhesives, primers, removers, and tools are compatible with the wall surface and wallpaper type. Read our advertising disclosure.
How this calculator works
Required strips are based on net wall area and strip coverage. Pattern repeat rounds each strip length up to a matching interval; rolls are rounded up from the usable strips per roll.
Pattern repeat changes usable coverage
A large vertical repeat can shorten the number of full-height strips cut from each roll. Match type—straight, drop, or random—also matters, so confirm the manufacturer’s ordering guidance.
Check how the product is packaged
Wallpaper may be priced as a single roll but packaged and sold as a double roll. Verify the physical roll length, not only the marketing description, before entering coverage and price.
Read the complete wallpaper planning guide: rolls, pattern repeat, and waste.
Wallpaper-room example
A 12-by-10-foot room with 8-foot walls has a 44-foot perimeter and 352 square feet of gross wall area. Subtracting large openings can help with a preliminary estimate, but roll quantity must be based on usable strips, not printed roll area alone. Pattern repeat, match type, trimming, ceiling height, roll length, and wall width determine how many full-height strips a roll supplies.
Count strips for the selected pattern
Measure each wall width and finished height, then add trimming allowance. Divide wall width by the installed paper width and round up to whole strips. Determine the cut length after adjusting for the pattern repeat, and divide the roll length by that cut length. Keep accent walls, different patterns, and production lots separate. Surface repair, primer, paste, tools, and extra material for future matching are outside the roll count.