Wallpaper Calculator

Work out how many physical rolls or bolts to buy using full-height strips, not just wall area. Enter the dimensions of the actual roll you will receive.

CurrencyUse one currency for all amounts. This changes labels only; it does not convert money or change local rules.

Measurement systemSwitching systems converts existing measurements.

Pattern matchUse the match type printed on the product. Quarter-drop, murals and pre-cut panels need a separate takeoff.

Wall 1 widthftEnter each wall separately. Use 0 for an unused wall.

Wall 2 widthft

Wall 3 widthft

Wall 4 widthft

Common wall heightftAll entered walls use this height. For mixed heights, estimate separate groups or use the highest height conservatively.

Physical roll widthinUse actual usable width. The default is an example, not a universal wallpaper size.

Physical roll lengthftLength of one physical roll/bolt, not the area or nominal single-roll price unit.

Total top + bottom triminCombined extra length on each strip. A value of 4 means 4 total, not 4 at each end.

Vertical pattern repeatinUsed for straight and half-drop matches only. Patterned estimates also reserve one full repeat at the start of every roll.

Extra full-height stripsstripsOptional spare strips added before rounding rolls. No additional hidden waste percentage.

Price per physical roll (optional)USDEnter 0 to omit cost. Match the price unit to the physical roll length above.

Calculation results

Physical wallpaper rolls

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How to use this calculator

Measure each wall

Enter up to four wall widths and a common height. Each wall gets its own rounded-up strip count so a narrow leftover strip is not assumed reusable around a corner.

Read the roll label

Enter the usable width and full length of the roll or bolt being supplied. Single-roll pricing does not always mean a single physical roll.

Allow for the pattern

Free match uses height plus trim. Straight and half-drop modes use a conservative repeated cut length and reserve one pattern repeat per roll for starting alignment.

Review strips and rolls

Choose any extra full-height strips, then check the strip yield and roll count. Openings are not deducted; shorter offcuts around windows or doors are not automatically reused.

Formula and worked example

Strips per wall = round up(wall width ÷ roll width)
Required strip length H = wall height + total trim
Free match cut length = H
Straight match cut length = round up(H ÷ repeat) × repeat
Half-drop planning length = straight-match length + half a repeat
Patterned usable roll length = roll length − one repeat
Strips per roll = round down(usable length ÷ planning cut length)
Rolls = round up((wall strips + spare strips) ÷ strips per roll)

For walls 12, 10, 12 and 10 feet wide, 20.5-inch paper requires 8 + 6 + 8 + 6 = 28 strips. An 8-foot wall plus 4 inches total trim gives an 8⅓-foot strip. A 33-foot free-match roll yields 3 full strips. With one spare strip, 29 ÷ 3 rounds up to 10 physical rolls. Pattern matching or different roll dimensions can change that count.

Why wall area alone can understate roll needs

Illustration: 8-ft walls, 4 inches combined trim and 29 required strips. Roll widths remain 20.5 inches. These are arithmetic examples, not product recommendations.
Same example, free match	Full strips per roll	Rolls for 29 strips
33-ft physical roll	3	10
40-ft physical roll	4	8
50-ft physical roll	6	5

Frequently asked questions

Should I subtract doors and windows?

Not in this full-height-strip model. Openings can create usable offcuts, but area subtraction alone does not show whether those offcuts match the pattern and fit the remaining spaces. Keeping openings included is conservative.

What does a double roll mean here?

Enter the length and price of the physical roll or bolt you will receive. A package sold or priced in single-roll equivalents can contain a longer physical roll. The calculator does not assume the seller’s naming convention.

How is half-drop matching handled?

The estimate rounds height plus trim up to whole repeats, then adds half a repeat to each planning strip. It also reserves one repeat at each roll start. This is a conservative quantity model, not a minimum-waste alternating-strip cutting plan.

What if the walls have different heights?

Run groups of equal-height walls separately and add the roll estimates, or use the highest height for a conservative single run. A professional cutting plan can sometimes reuse lengths across groups.

Why does adding one spare strip sometimes add a whole roll?

Wallpaper is purchased in complete physical rolls. If the original roll allocation has no capacity for another full-height strip, one extra strip requires another roll. The breakdown shows capacity after rounding.

Methodology and sources

This is an Efficienco strip-planning model informed by manufacturer definitions of roll size, pattern repeat and match. Its alignment reserve and constant half-drop planning length are explicit conservative assumptions, not a manufacturer-prescribed formula. It excludes offcut reuse, split drops around openings, corner overlap, trimming the roll edges, murals and custom panels. Confirm the final takeoff, usable width and batch requirements before ordering.

Brewster — wallpaper properties — Definitions of match types and single-roll versus bolt packaging.
Boråstapeter — measuring wallpaper requirements — Which wall, roll and pattern dimensions to obtain from the product specifications.
NIST Handbook 44 — measurement tables — Length and area unit conversions.

Sources checked September 1, 2026. Referenced organizations do not endorse Efficienco. Calculations retain full precision until display; purchase units round up.