Floors & Walls

Wallpaper Calculator

Estimate wallpaper strips and rolls using real roll geometry — not just wall area.

Units

Your measurements

Results update as you type.

Example shown — use your own measurements.

Sum of wall widths of equal height. Walls of different heights are separate groups — run the tool per height and add the rolls.

Additional walls (optional — different heights are priced as separate roll groups)

1.
Extra options & cost (optional)

Top + bottom cutting allowance added to each strip.

Straight match only. Each cut length rounds up to a whole repeat.

Subtracts from reported net wall area. Full-height strips are retained for ordering so pattern matching around openings is not understated.

Fractions and number formats

Use decimals (12.5), fractions (12 1/2 or 12-1/2), or explicit lengths (12ft 6in, 12′ 6″, 25 mm). A comma followed by one or two digits is a decimal comma: 12,5 = 12.5. Grouped commas mean thousands: 1,200 = 1200. Use a decimal point for ambiguous values. Scientific notation is not accepted.

Enter your measurements

Results update as you type.

About this calculator

Estimate whole wallpaper rolls from wall dimensions, roll size, trim and straight-match repeat. Compare net wall area after door/window area deductions while retaining conservative full strips for ordering.

How to measure

  • Measure each wall's full width, corner to corner or corner to trim.
  • Measure the height at both ends and the middle — use the largest figure.
  • Add each extra wall with its own height; walls of the same height share a roll pool automatically.
  • Check the roll label for usable width, roll length and pattern repeat before buying.

How to use this calculator

  1. Measure total width of walls that share one height, and that height.
  2. Enter the roll width and length from the product label.
  3. Enter the pattern repeat for straight-match patterns, or 0 for random match.
  4. Run the tool again for walls of a different height and add the rolls.

Formula

Strips = ⌈wall width ÷ roll width⌉

Cut length = height + trim, rounded up to the next repeat multiple when repeat > 0

Strips per roll = ⌊roll length ÷ cut length⌋; rolls = ⌈strips ÷ strips per roll⌋

Assumptions

  • Opening area reduces reported net area only. Full-height strips are retained for conservative purchasing around doors and windows.
  • Straight-match and random-match only; half-drop patterns are not supported and would need more paper.
  • Rolls are never estimated by dividing gross wall area by gross roll area — that understates the need.

Example 10 m roll, 0.5 m wide

Example 10 m roll, 0.5 m wide
Cut length including trim/repeatWhole strips per roll
2 m5
2.5 m4
2.6 m3

Whole strips = floor(roll length ÷ cut length). Drop matching and offcut reuse require a layout.

Common mistakes

  • Subtracting opening area as though every full strip disappears.
  • Leaving pattern repeat out of the cut length.
  • Assuming strips of different heights can always share offcuts.

Worked example

Try it: press “Load example” above the form.

A 4 m wall of 2.4 m height needs 8 strips of 2.6 m; a 10 m roll yields 3 strips, so buy 3 rolls.

Limitations

Straight pattern matching and full-height strip purchasing. Door/window area reduces reported net wall area only; it does not automatically remove full strips. Drop matches, murals and offcut reuse need a separate cutting layout.

Frequently asked questions

Should I subtract windows and doors from wallpaper rolls?

Not automatically from area. Full-height strips may still be needed beside openings and for pieces above or below them. Enter opening area for net wall area only; the conservative strip count keeps full strips to preserve matching.

What pattern matching does this model support?

Straight matching: each strip length rounds up to a whole pattern repeat after adding trim. Drop matching, numbered murals and reusing small offcuts require a separate layout.

What does the worked example show?

A 4 m wall of 2.4 m height needs 8 strips of 2.6 m; a 10 m roll yields 3 strips, so buy 3 rolls.

Which assumptions should I check before using the result?

Straight pattern matching and full-height strip purchasing. Door/window area reduces reported net wall area only; it does not automatically remove full strips. Drop matches, murals and offcut reuse need a separate cutting layout.

Reviewed by Codex AI editorial agent (Editorial, 2026-11-12).

Sources

Sources explain the methods and any named product presets. Check your product label where coverage, yield or density differs.

Calculation documentation · Updated 2026-11-08 · Version 1.6.4. Estimates are planning aids. Confirm quantities, coverage and prices with your supplier before purchasing. Found an error? Report it.

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