◆ Calculators ◆ Wallpaper Calculator: Rolls Needed by Wall Size & Pattern Repeat
Wallpaper Calculator: Rolls Needed by Wall Size & Pattern Repeat
Calculate the number of wallpaper rolls needed from wall perimeter, ceiling height, your own roll size, and the pattern repeat.
No default is set — measure the width and length printed on the roll label you plan to buy. York Wallcovering produces paper on two roll sizes: 20 1/2 inches wide by 33 feet long and 27 inches wide by 27 feet long. There is approximately the same amount of square footage on each roll, but strip yield differs — enter your own roll's numbers.
No default is set — measure the width and length printed on the roll label you plan to buy. York Wallcovering produces paper on two roll sizes: 20 1/2 inches wide by 33 feet long and 27 inches wide by 27 feet long. There is approximately the same amount of square footage on each roll, but strip yield differs — enter your own roll's numbers.
Leave at 0 for a plain (non-patterned) wallpaper. York Wallcoverings: 'larger pattern repeats will require more wallpaper rolls.' This calculator assumes a straight match — every strip starts at the same point in the pattern, so the usable length of a roll is rounded down to a whole multiple of the repeat. This rounding rule is this calculator's own method, not a figure quoted by the manufacturer.
No source checked for this calculator names a waste percentage for wallpaper — 0% is a starting point, not a claim that no waste occurs. A retailer (not the manufacturer) quotes 10% for its own estimates; adjust this field yourself if your project needs more.
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How the number is worked out
The steps from input to result
This calculator gives you five separate numbers because they answer different questions. Wall area, Strips needed, Strip length (after repeat), and Strips per roll are the geometric steps that lead to the actual purchasing quantity: Rolls needed. The result you buy by is Rolls needed, not the wall area — wallpaper is bought and hung in vertical strips, not sold by the square foot.
York Wallcovering produces paper on two roll sizes: 20 1/2 inches wide by 33 feet long and 27 inches wide by 27 feet long. Because roll width and roll length are not standardized across the industry, this calculator does not assume either for you — measure your own roll's label and enter both numbers.
Wallpaper is priced in a way that can trip up a first-time buyer. York Wallcoverings: WALLPAPER IS PACKAGED IN BOLTS · 1 BOLT = 56 FT² {20.5 IN X 33 FT}. And: Why is wallpaper priced by the single roll and sold in double rolls? […] the single roll, as the minimum measurement, remained the pricing standard. Rolls needed always counts in the same unit you measured above — the roll or bolt as printed on the label — never automatically a 'single roll', so check your label before ordering.
A patterned wallpaper needs more material than a plain one. York Wallcoverings: larger pattern repeats will require more wallpaper rolls. This calculator assumes a straight match, where every strip starts at the same point in the pattern — the usable length of each roll is rounded down to a whole multiple of the repeat you enter. That rounding rule is this calculator's own method, not a number quoted by the manufacturer.
Doors and windows are not deducted automatically, because whether an opening actually saves a whole strip depends on where it falls on the wall — information this calculator does not have. York Wallcoverings offers only a rule of thumb: Deduct 1 bolt for every 4 ordinary size door or window. Apply it yourself if it fits your room.
The formula
Written out, so you can check it by hand
Strips needed = round up( wall perimeter ÷ roll width ). Strip length = ceiling height, or — if a pattern repeat is set — round up( ceiling height ÷ repeat ) × repeat, so every strip starts at the same point in the pattern. Strips per roll = round down( roll length ÷ strip length ). Rolls needed = round up( strips needed × (1 + waste allowance ÷ 100) ÷ strips per roll ) — the waste allowance applies before this final rounding, not after.
Worked example
Worked with the preset values
For a 52 ft wall perimeter and an 8 ft ceiling with a 20.5 in × 33 ft roll and no pattern repeat: strips needed = round up(52 ÷ 1.7083) = round up(30.44) = 31 strips. Strip length stays 8.00 ft (no repeat). Strips per roll = round down(33 ÷ 8) = round down(4.125) = 4. Rolls needed = round up(31 × 1.00 ÷ 4) = round up(7.75) = 8 rolls. With a 21 in pattern repeat instead, strip length becomes round up(8 ÷ 1.75) × 1.75 = 5 × 1.75 = 8.75 ft, strips per roll drops to round down(33 ÷ 8.75) = 3, and rolls needed rises to round up(31 ÷ 3) = 11 rolls — the pattern repeat alone moves the order from 8 to 11 rolls.
What this calculator does not do
Named, not left out
- 01Rolls needed counts in the unit you measured for roll width and roll length — not automatically a 'single roll'. York Wallcoverings: WALLPAPER IS PACKAGED IN BOLTS · 1 BOLT = 56 FT² {20.5 IN X 33 FT}, and single rolls remained the pricing standard even though wallpaper is sold in double rolls — check your own label before ordering.
- 02The manufacturer's own room-size table is not used as the calculation method here: it is not reproducible from any single formula (it neither accounts for a pattern repeat nor for waste), so it is cited only as evidence for which four inputs matter, not as a lookup table.
- 03Only a straight pattern match is calculated. A drop match or half-drop pattern can require more wallpaper than a straight match, but no source checked for this calculator gives a number for how much more — no figure is invented here.
- 04Doors and windows are not deducted automatically. York Wallcoverings offers only a rule of thumb: Deduct 1 bolt for every 4 ordinary size door or window. Whether an opening actually saves a whole strip depends on where it falls on the wall, which this calculator does not know.
- 05No trim allowance for pattern matching at the top and bottom of each strip is built into this calculator — no source checked for this calculator quantifies one. Add it yourself through the waste allowance or the ceiling height if your installer recommends extra.
- 06This calculator works entirely in US units (ft, in). A metric roll size (around 52 to 53 cm by 10.05 m) is documented only by a retailer, not by the manufacturer, and is not built in here.
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Updated: 9/16/2026