Wallpaper Calculator
Size up to eight walls with door and window deductions. Use the WA yield table or strip counting when repeat and roll length matter.
FAQ
Why does the default room show 16 rolls?
Four 12×8 ft walls are 384 ft² gross. One 21 ft² door and two 12 ft² windows leave 339 ft² net. An 8-inch repeat maps to 22 ft² per metric single roll on the WA table, and 339 ÷ 22 rounds up to 16 rolls.
When should I use strip count instead of area yield?
Area yield is fast for planning. Strip count follows roll width, cut length, half-drop sequencing, and per-wall drops—use it when the repeat is large, the roll is short, or you need to match a supplier roll length.
What roll sizes are built in?
Metric single (20.5 in × 16.5 ft), metric double (33 ft long), and American single (21 ft with a fixed 30 ft² yield in area mode). Strip mode lets you edit roll width and length in inches.
Does area yield match strip count?
Not always—they answer different questions. The default four-wall room is 16 rolls in area mode but strip mode with zero trim can differ; pick the method that matches how you will hang.
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By Home Yard Calc Editorial Team · Sources listed on the methodology page · Last updated October 26, 2026
Estimates only. Densities, coverage and salt targets vary by product, moisture and manufacturer. Confirm with your supplier or equipment manual. Not a substitute for professional design, soil engineering or pool service.