Calc4Living

Home Renovation · Free calculator

Wallpaper Calculator

Estimate rolls for one rectangular wall from full-height strips, roll dimensions, pattern repeat, trimming and spare-strip allowance.

Your project inputs

Prefilled measurements and product coverage are editable examples, not product or structural recommendations. All fields are required unless marked optional.

Changing units converts current measurements, product coverage and price per area. Results clear when any input changes.

Measured dimension in the selected unit.

Measured dimension in the selected unit.

Combined opening area for net-area display only. Roll counts conservatively retain strips above/below openings. Blank = 0.

Use the actual roll width, not its area.

Length printed on the roll; remove any known unusable end length.

Blank or 0 for free/random match. Offset/half-drop patterns are not modeled.

Combined top and bottom trim, not trim at each end. Blank = 0.

Optional extra material added to the estimate. Blank or 0 means no allowance.

Your estimate

Materials & purchasing quantities

Review the example values, enter your measurements and product specifications, then calculate. Results clear whenever inputs change.

How many wallpaper rolls do I need for one wall?

Strips across wall = ceiling(wall width ÷ roll width). Cut length = wall height + total trimming allowance. For straight match, round cut length upward to a whole pattern repeat. Usable strips/roll = floor(roll length ÷ cut length). Add waste as extra whole strips, then rolls = ceiling(total strips ÷ strips/roll).

Worked example

A 4 m wide, 2.5 m high wall needs eight strips of 0.53 m width. Adding 0.10 m total trim and a 0.53 m straight-match repeat gives a 2.65 m cut length. A 10 m roll yields three strips. A 10% spare-strip allowance raises eight strips to nine: three rolls. A 1 m² opening reduces displayed net area to 9 m², but does not reduce this conservative strip count.

Unit conversions

1 ft = 0.3048 m; 1 in = 0.0254 m; 1 cm = 0.01 m. Area conversions use squared length factors, and volume conversions use cubed factors. 1 yd³ = 27 ft³ = 0.764554857984 m³; 1 L = 0.001 m³.

Assumptions & limitations

  • Combined door/window area reduces displayed net area only. Roll quantities conservatively keep full-height strips for paper above and below openings; no opening offcuts are reused. An entirely unpapered wall (net area zero) requires no rolls.
  • Supports free/random match (repeat 0) and straight match. Assumes each roll starts at a usable pattern position and is fully usable; any initial alignment loss must be included in trim/waste. Offset/half-drop matches, A/B designs and murals require a product-specific layout.
  • Calculate each wall separately; adding widths together can miss corner cuts. Sloped walls, varying heights, batch differences, damaged roll ends and partial-strip reuse are not modeled.
  • A roll shorter than one pattern-adjusted full-height strip cannot be used in this model. Waste adds spare strips before whole-roll rounding; it is not an area-only roll estimate.

Manufacturer guidance on measuring walls and wallpaper match types