Wallpaper Calculator: Free and Accurate

Wallpaper Roll Estimator

Enter the room size and your pattern repeat. The estimator adjusts roll coverage for pattern waste automatically.

Room length

Room width

Ceiling height

Doors and windows

doors windows

Pattern repeat

Roll size

Your Estimate

0 rolls to buy

Wall area to paper-

Pattern waste allowed-

Effective coverage per roll-

Estimated paper cost-

Cost uses $50 to $120 per double roll for common residential wallpaper, national retail pricing checked October 2026 (halve it for single rolls). Grasscloth, designer and imported papers cost far more. Paste, primer and tools are extra.

The Formula Behind This Calculator

Wall area = 2 x (length + width) x ceiling height - (doors x 21 sq ft) - (windows x 15 sq ft)

Effective roll coverage = roll coverage x (1 - pattern waste %)

Pattern waste: none 15%, up to 12 in repeat 20%, up to 18 in 25%, up to 24 in 30%, larger 35%

Rolls = round up (wall area / effective roll coverage)

There are two honest ways to estimate wallpaper: strip by strip, or by area with a waste factor. This calculator uses the area method with a waste factor that grows with the pattern repeat, because it matches how the major paper makers publish their own charts. The repeat matters because each strip is cut long, then trimmed back so the pattern aligns with its neighbor, and the bigger the repeat, the more of each strip ends up in the trash. Even a plain paper wastes about 15 percent on trimming tops and bottoms, fitting around outlets, and the occasional torn strip, which is why the no repeat setting is not zero.

Worked Example: A 12 by 10 Room With an 18 Inch Repeat

A bedroom is 12 feet by 10 feet with 8 foot ceilings, one door and one window. The paper is a standard US double roll, 20.5 inches wide by 33 feet long, with an 18 inch pattern repeat.

Gross wall area: 2 x (12 + 10) x 8 = 352 square feet.
Subtract openings: 352 - 21 - 15 = 316 square feet to paper.
Roll coverage: 20.5 inches is 1.71 feet, x 33 feet = about 56 square feet per double roll.
Pattern waste at an 18 inch repeat: 25 percent, so effective coverage is 56 x 0.75 = about 42 square feet.
Rolls: 316 / 42 = 7.5, round up to 8 double rolls.
Budget: 8 rolls at $50 to $120 is $400 to $960 for the paper, in October 2026 national retail pricing.

Change the repeat to plain in the tool and the same room drops to 7 rolls. That single roll difference is the hidden price of a bold pattern, and it is worth knowing before you fall for a large motif design in the showroom rather than after the first roll is cut.

A Complete Guide to Estimating Wallpaper Without Running Short

Wallpaper has a failure mode no other material shares: you cannot fix a shortage with a quick store run, because the paper on the shelf next month may be a different production run with a slightly different color. Estimating generously and buying once, from one run, is the whole game. This guide covers the repeat, the roll sizes, and the rooms that break the standard math.

Understand the Three Match Types

Random match papers, including most textures, grasscloth looks and plains, have no pattern to align, so strips can be cut to exact length and waste stays near the 15 percent trimming allowance. Straight match papers repeat the same point at the same height on every strip, which is simple to hang but forces each cut to the next full repeat. Drop match, also called half drop, shifts each strip by half a repeat, which looks more natural for large designs and wastes the most, because the alignment point walks down the roll as you cut. The repeat length and the match type are both printed on the label. When in doubt, estimate with the next waste band up: the difference is usually one roll, and one roll is cheap compared to a wall finished in two shades.

Rooms That Break the Standard Math

Stairwells have a long diagonal wall where strips run far taller than the ceiling height at the low end, and they should be measured strip by strip rather than by room perimeter. Rooms with chair rail or wainscot only paper the upper section, so use the papered height instead of the full ceiling height by treating the job as a shorter room. Accent walls are the easiest estimate of all: measure the one wall, divide by effective roll coverage, and round up. Vaulted ceilings and angled dormer walls add triangular sections; measure each as its own rectangle using the tallest height and allow the extra waste band, because nearly every strip ends in a diagonal cut.

What Wallpaper Costs in 2026

As of October 2026, based on national retail pricing, common vinyl and non woven wallpaper runs about $50 to $120 per double roll. Designer brands and grasscloth commonly run $150 to $300 per roll or more, and murals are priced per panel. Supplies add up quietly: a gallon of wallpaper primer or sizing is $20 to $35, paste is $15 to $25 if the paper is not prepasted, and a basic hanging kit with a smoothing brush, seam roller and sharp blades is $25 to $40. Professional hanging typically costs $300 to $600 per average room in published surveys, more for stairs and high ceilings. Against those numbers, the extra spare roll is the cheapest insurance in the whole project.

Buying and Hanging Rules

Check the run or dye lot number on every roll before opening any of them, and buy all rolls in one order.
Unroll and inspect the first roll in daylight. Printing flaws repeat down the roll and are much easier to exchange unhung.
Cut strips for a full wall before pasting any of them, checking the pattern alignment across the set.
Keep the extra roll and a note of its run number stored flat and dry. It is the only true match for a future repair.
For a first project, choose a random match or small repeat paper. The hanging is the same, but your cutting mistakes get far cheaper.

Frequently Asked Questions

How many rolls of wallpaper do I need for a 12 by 10 room?

With 8 foot ceilings, one door and one window, the papered area is about 316 square feet. A standard US double roll covers about 56 square feet before pattern waste. With an 18 inch pattern repeat wasting about a quarter of each roll, the effective coverage is near 42 square feet, so plan on 8 double rolls. A plain or random match paper wastes less and might do the same room in 7 rolls, while a large 24 inch repeat can push it to 9.

What is the difference between a single roll and a double roll?

Wallpaper is priced by the single roll but usually sold and shipped as a double roll, which is one continuous roll twice as long. A typical US single roll is about 20.5 inches wide and 16.5 feet long, covering about 28 square feet, and the double roll is 33 feet long covering about 56 square feet. European rolls are a different size again, about 20.5 inches by 33 feet is common there too, but always estimate from the width, length and coverage printed for the exact paper you are buying.

How does pattern repeat change how much wallpaper I need?

Every strip must start at the same point in the pattern so the design lines up across the wall. That means each strip is cut longer than the wall, rounded up to the next full pattern repeat, and the offcut is usually waste. A random match or plain paper wastes about 15 percent for trimming and fitting. A 12 inch repeat wastes around 20 percent, an 18 inch repeat about 25 percent, and a bold 24 inch repeat about 30 percent or more, which the calculator builds into the effective coverage.

Should I subtract doors and windows from the wallpaper area?

Yes for planning, with a small caution. Standard doors remove about 21 square feet and typical windows about 15 square feet of papered area, and the strips above and below a window use short cuts that often come from roll ends. Subtracting standard openings the way this calculator does gives a realistic roll count for typical rooms. If a wall is mostly glass or has floor to ceiling built ins, measure the actual papered sections instead of using the room perimeter.

How many rolls should I order beyond the estimate?

Order one extra roll if your budget allows it, from the same production run. Wallpaper is printed in runs, also called dye lots, and a roll printed later can be a shade off in a way that only shows after hanging. An extra roll covers a damaged strip repair years from now, and an unopened roll from the same run is far easier to live with than a discontinued pattern. Check every roll carries the same run number before you open any of them.

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