Wallpaper Roll Chart: Rolls Per Wall & Repeat Waste 2026

The repeat eats a drop — and that is the whole chart

Wallpaper comes in rolls 20.5 inches wide and 33 feet long (a single roll; a double roll is 66 feet long). You cut the roll into strips as tall as the wall, so the first question is how many strips fit across the wall: wall width divided by 1.7083 feet, rounded up. The second question is how many strips each roll gives you, and that is where the pattern repeat bites: each strip is cut a little longer than the wall height, because the pattern has to line up with the strip next to it. Drop length = wall height + pattern repeat / 12. A 33-foot roll gives floor(33 / drop) drops. Rolls = strips / drops per roll, rounded up. On the defaults — wall 12 ft wide, 8 ft high, pattern repeat 12 in, roll type single — the drop is 9.00 ft, a roll gives 3 drops, the wall needs 8 strips, and the answer is 3 rolls. The wall area is 96 sq ft — but the roll area is not the answer, because the repeat wastes a drop per roll.

At the defaults — wall width 12 ft, wall height 8 ft, pattern repeat 12 in, roll type single — the drop length is 9.00 ft, the drops per roll are 3, the strips needed are 8, the rolls are 3, and the wall area is 96 sq ft. Check the identities: drop length = wall height + pattern repeat / 12; drops per roll = floor(roll length / drop length); strips needed = wall width / 1.7083 ft, rounded up; rolls = strips / drops per roll, rounded up. A single roll is 20.5 in wide × 33 ft long (56.37 sq ft gross); a double roll is 66 ft long (112.75 sq ft). Rounding convention: totals are computed from unrounded values, so rounded parts may differ by a cent from their rounded sum.

The worked example, line by line

Setup: wall width 12 ft, wall height 8 ft, pattern repeat 12 in, roll type single.

Line 1 — the drop length. 8 ft + 12 in / 12 = 8 + 1 = 9.00 ft. Each strip is cut 9 feet long, so the pattern lines up with the strip next to it.

Line 2 — the drops per roll. floor(33 / 9.00) = floor(3.67) = 3 drops. The roll gives 3 strips and 6 feet are left over — not enough for a fourth drop.

Line 3 — the strips needed. 12 ft / 1.7083 ft = 7.03, rounded up to 8 strips. Seven strips cover 11.96 feet, so an eighth strip is needed for the last few inches.

Line 4 — the rolls. 8 strips / 3 drops per roll = 2.67, rounded up to 3 rolls.

Line 5 — the check. Three rolls give 9 strips, one more than the 8 needed — the spare strip covers a miscut or a bad match. The wall area is 96 sq ft, but three single rolls are 169.11 sq ft gross: the difference is the repeat waste and the leftover strip ends.

Reverse: 3 rolls at a 12-inch repeat on an 8-foot wall cover 9 strips, so the widest wall that still needs 3 rolls is 15.37 ft (exact 15.3747 ft); at that width the strips are 9 and the rolls are 3. At 15.38 ft the strips are 10 and the rolls are 4. The 96 sq ft headline wall takes 3 rolls.

Every branch, checked

Pattern repeat 0 in: drop 8.00 ft, 4 drops per roll, 8 strips — 2 rolls. With no pattern repeat to match, the drop is 8.00 ft, so a roll gives 4 drops: 8 strips need only 2 rolls — the repeat was costing a whole roll.

Pattern repeat 24 in: drop 10.00 ft, 3 drops per roll, 8 strips — 3 rolls. With a 24-inch repeat the drop is 10.00 ft, so a roll still gives 3 drops and the answer stays 3 rolls — the repeat has to push the drop past 11 ft before a drop is lost.

Wall 10 ft wide: drop 9.00 ft, 3 drops per roll, 6 strips — 2 rolls. A 10-foot wall needs 6 strips, and at 3 drops a roll that is 2 rolls — two feet narrower saves a roll.

Wall 15 ft wide: drop 9.00 ft, 3 drops per roll, 9 strips — 3 rolls. A 15-foot wall needs 9 strips, and at 3 drops a roll that is 3 rolls — the same as the 12-foot wall, because 9 strips still fit in 3 rolls.

Wall 9 ft high, repeat 12 in: drop 10.00 ft, 3 drops per roll, 8 strips — 3 rolls. A 9-foot wall with a 12-inch repeat has a 10.00 ft drop, so a roll gives 3 drops and the answer stays 3 rolls.

Wall 10 ft high, repeat 0 in: drop 10.00 ft, 3 drops per roll, 8 strips — 3 rolls. A 10-foot wall with no repeat has a 10.00 ft drop, so a roll gives 3 drops and the answer stays 3 rolls.

Double roll (66 ft): drop 9.00 ft, 7 drops per roll, 8 strips — 2 rolls. A double roll is 66 feet long, so it gives 7 drops: 8 strips need only 2 rolls — one double roll nearly does the whole wall.

Wall 20 ft wide: drop 9.00 ft, 3 drops per roll, 12 strips — 4 rolls. A 20-foot wall needs 12 strips, and at 3 drops a roll that is 4 rolls — the widest wall in the chart.

Pattern repeat 18 in: drop 9.50 ft, 3 drops per roll, 8 strips — 3 rolls. With an 18-inch repeat the drop is 9.50 ft, so a roll still gives 3 drops and the answer stays 3 rolls.

What the defaults assume

The model assumes a standard roll 20.5 inches wide and 33 feet long for a single roll, 66 feet for a double roll. It assumes each strip is cut to the drop length — wall height plus the full pattern repeat — so the pattern lines up with the strip next to it. It assumes no allowance for windows, doors or outlets: measure the full wall width and subtract nothing, because the offcuts from around a window rarely line up with the pattern. It assumes the same dye lot for every roll; if you buy an extra roll later, the colour may not match. With a wall width of 0 the answer is 0 rolls. With a wall height of 35 ft the drop is 36.00 ft — longer than the 33-foot roll — so the drops per roll are 0 and the answer is — (the roll is too short; a 35-foot wall needs a longer roll or a horizontal hang). Rounding convention: totals are computed from unrounded values, so rounded parts may differ by a cent from their rounded sum; the reverses are nearest-value solutions, and the exact unrounded figures (15.3747 ft) are stated wherever the rounded figures appear.

Output · formula · meaning

Who uses this

• The homeowner wallpapering a 12-foot bedroom wall: they learn it takes 3 rolls — 8 strips at 3 drops a roll — and they check the repeat-0 branch (2 rolls) to see what a pattern-free paper would save.
• The renter papering one 20-foot feature wall: they learn it takes 4 rolls — 12 strips — and they check the double-roll branch (2 rolls) before deciding whether the longer rolls are worth it.
• The DIYer with a 15.38-foot wall: they learn the wall needs 10 strips and 4 rolls, not 3 — the widest wall that still takes 3 rolls is 15.37 feet — and they check the 15-foot branch (3 rolls) to see how close they are.
• The renovator with 10-foot ceilings: they learn a 12-foot wall takes 4 rolls with a 24-inch repeat, not 3 — and they check the 10-foot, repeat-0 branch (3 rolls) to see what the repeat costs.

Accuracy & limitations

The math is exact arithmetic on your four inputs: drop length = wall height + pattern repeat / 12; drops per roll = floor(roll length / drop length); strips needed = wall width / 1.7083 ft, rounded up; rolls = strips / drops per roll, rounded up. The 4-decimal exact is shown where the rounding matters: 9 strips cover 15.3747 ft (shown as 15.37 ft); at 15.38 ft the wall needs 10 strips and 4 rolls. What the model cannot do is count the paper for windows, doors and outlets — measure the full wall and let the offcuts fall where they may — or match dye lots across separate purchases. For the paint version, see the paint drying time chart; for the room underneath, see the joist span chart; for the wall underneath, see the drywall screw spacing chart. This is a calculator, not a decorating guide.