Wallpaper Calculator
Find out how many rolls of wallpaper you need to buy for a room.
Room dimensions
Results
For a 12 ft × 10 ft room with 8 ft walls, 1 door, and 2 windows, papered with a plain wallpaper, you'll need about 6 double rolls.
Wallpaper rolls needed
6 rolls
That's a typical amount for a standard bedroom, living room, or dining room.
Buy every roll in a single order rather than reordering later — wallpaper runs change over time, and a second order risks a subtle color or texture mismatch you can't correct once the first rolls are hung.
Wall area: 304 sq ft
Area including waste allowance: 334 sq ft
How this works
Wall area is calculated the same way as BuildyWork's paint calculator: the room's perimeter times wall height, minus a standard opening size for each door and window you enter (about 17 sq ft per door, 15.5 sq ft per window). A waste allowance is then added on top of that raw area — 10% by default for plain wallpaper, 15% for patterned, since patterned paper needs extra material to align its repeat across strips. Both defaults sit at the top of their commonly cited industry ranges (roughly 5-10% for plain, 10-15% for patterned) rather than the middle, on the assumption that most users are estimating for a single purchase rather than iterating with a professional installer on-site, so a slightly generous default is more useful than a tight one that risks a mid-job store run. The resulting area is divided by a roll's usable coverage (56 sq ft for a standard US double roll by default) to get the raw number of rolls needed, then rounded up to the next whole roll, since wallpaper is sold in whole rolls. This model treats every strip as needing the full waste percentage uniformly, which is a simplification: in reality, waste concentrates at cut points (ceiling line, floor line, around openings, and pattern-match seams) rather than being spread evenly across the roll, so a room with unusually many small interruptions or an irregular ceiling line will waste more than this flat-percentage model predicts, while a large uninterrupted wall will waste somewhat less. As with the paint calculator, this single-rectangle model works well for typical rectangular rooms and slightly overestimates for rooms with alcoves or jogs that remove area the model can't account for without you explicitly excluding it. The unit toggle above switches every input and result between imperial (feet, sq ft) and metric (metres, m²) — internally, every calculation always runs in the same canonical units regardless of which one you're viewing, so switching back and forth never introduces rounding drift into your entered values. Standard US double-roll coverage (56 sq ft) and pattern-repeat waste guidance: York Wallcoverings installation guide.
Worked example
A 12 ft × 10 ft bedroom with 8 ft ceilings, one door, and two windows, papered with a plain (non-repeating) wallpaper at the default 56 sq ft double-roll coverage and a 10% waste allowance: wall area works out to about 304 sq ft (352 sq ft of gross wall, minus roughly 48 sq ft for the door and windows). Adding 10% waste brings that to about 334 sq ft, and dividing by 56 sq ft per double roll gives about 5.97 rolls — rounded up to 6 double rolls, since wallpaper is sold as whole rolls.
A second example: a patterned wallpaper in a larger room
A 16 ft × 13 ft dining room with 9 ft ceilings, one door, and three windows, papered with a patterned wallpaper at the same 56 sq ft double-roll coverage but a 15% waste allowance for pattern matching: gross wall area is 2 × (16 + 13) × 9 = 522 sq ft. Subtracting one door (17 sq ft) and three windows (3 × 15.5 = 46.5 sq ft) leaves about 458.5 sq ft of paperable wall. Adding 15% waste brings that to about 527.3 sq ft, and dividing by 56 sq ft per roll gives about 9.42 rolls — rounded up to 10 double rolls. Compare this to the same room papered in a plain pattern (10% waste): about 484.5 sq ft ÷ 56 ≈ 8.65, rounding up to 9 rolls — one fewer roll, illustrating why pattern choice affects the shopping list, not just the look.
Common mistakes
Buying single rolls when the product is priced as a double roll (or vice versa)
Wallpaper listings sometimes state price 'per single roll' even when the product only ships as a double roll (two single rolls bonded together), which can make buyers order half of what they need. Always confirm the physical unit you're purchasing — the roll count on your receipt, not just the price label — against this calculator's roll-coverage assumption before finalizing your order.
Ignoring the pattern repeat size when choosing a waste allowance
This calculator offers plain vs. patterned as a simple toggle, but repeat size varies a lot within 'patterned' — a small 6-inch repeat wastes much less than a 24-inch repeat. If your chosen pattern lists an unusually large repeat on its spec sheet, manually increase the waste allowance in Advanced settings beyond the 15% patterned default.
Not accounting for a chimney breast, alcove, or bay window
Like the paint calculator, this tool models a simple rectangular room. Rooms with a jutting chimney breast or a bay window have more wall surface (and more corners to match pattern across) than a flat rectangle of the same footprint — measure these features as additional small rectangles and add their area manually rather than trusting the single length × width estimate.
Ordering from mismatched dye lots
Wallpaper, like paint, is manufactured in batches (often called 'run' or 'lot' numbers), and color can shift subtly between runs. Order your entire roll count in one purchase and confirm every roll shares the same lot number before hanging — a lot mismatch is far more visible on a patterned wall than a paint color mismatch is on a painted one.
Forgetting that wallpaper waste isn't reusable scrap
Unlike paint, where a half-used can is still useful next time, trimmed wallpaper offcuts are rarely large enough to reuse elsewhere in the room once the pattern has been cut to match. Don't assume a generous waste allowance means you'll have usable leftover material for a future patch repair — keep at least one full extra roll unopened for that purpose instead.
Measuring over existing wallpaper without accounting for removal
If you're papering over old wallpaper (not recommended by most manufacturers) or need to strip it first, budget separate time and possibly a different adhesive primer step — this calculator estimates paper quantity only, not the surface-prep material or time a removal job adds.
Cutting all strips before hanging the first one
Pre-cutting a full room's worth of strips before hanging any of them assumes every strip needs the same length, but pattern-matching against the previous strip and small variations in ceiling height (real rooms are rarely perfectly level) mean each strip's ideal cut length can differ slightly. Cutting and hanging one or two strips at a time, matching each to what's already up, wastes less paper than committing to a full batch of identical pre-cut lengths.
Not checking the pattern's match type before ordering
Wallpaper repeats come in different match types — straight match (the pattern lines up horizontally across adjoining strips) versus drop match (the pattern offsets vertically between strips, common in organic or diagonal designs). Drop-match patterns generally waste more material than straight-match patterns at the same repeat size, since usable full-height cuts occur less often. Check the product's listed match type, not just its repeat size, before assuming the standard patterned waste allowance covers it.
Not confirming ceiling height at multiple points before ordering
Real ceilings are rarely perfectly level across an entire room's length — a difference of an inch or two between one end of a wall and the other is common in older homes. Measuring height at only one point and assuming it holds across the whole room can leave the last strip on the low end of an unlevel wall too short. Measure at both ends of each wall and use the taller figure as your wall height input, since a slightly generous height entry costs little extra material but a short one requires a mid-job course correction.
When this calculator's model stops applying
- Vaulted or sloped ceilings: this tool assumes a flat wall height entered once. For a room with an angled wall (a dormer, a cathedral ceiling wall), measure that wall's average height and expect the estimate to run slightly low.
- Large-repeat patterns (over roughly 20-24 inches): the 15% patterned default may undershoot. Increase the waste allowance manually in Advanced settings for very large repeats, and always buy from the same dye lot when doing so since large orders are more likely to span multiple production runs.
- Very large open-concept spaces (over roughly 500 sq ft of continuous wall): at this scale, small per-wall measurement errors compound, and pattern matching across many strips increases the odds of a visible seam. Measure and sum individual wall segments rather than one length/width estimate for the whole space.
- Textured or heavily patched walls: wallpaper (especially vinyl and non-woven types) telegraphs surface texture through the paper once hung. Skim-coat and sand heavily textured walls before measuring for paper, since this calculator only estimates quantity, not surface prep.
- Grasscloth and other natural-fiber wallcoverings: these often have wider manufacturing tolerances and visible natural variation between rolls, so professional installers commonly recommend an even larger buffer (beyond this calculator's patterned default) for these specific materials — check the manufacturer's own installation guide.
- Ceilings and stairwells: this calculator computes wall area only (see the FAQ above) and doesn't model the extra waste and difficulty of papering a raked stairwell wall, which typically needs a larger buffer than a standard flat wall of the same area.
- Rooms with many small interruptions (light switches, sconces, built-in shelving): each interruption forces an extra cut and pattern-match point that a smooth, uninterrupted wall wouldn't need. This calculator's opening subtraction only accounts for doors and windows — for a wall with several smaller fixtures, budget a few extra percentage points of waste beyond the plain/patterned default.
- Drop-match patterns: as noted in the Common Mistakes section, a drop-match repeat wastes more material than a straight-match repeat of the same size because fewer full-height strips align without an offset cut. This calculator's plain/patterned toggle doesn't distinguish match type — for a drop-match product, manually increase the waste allowance beyond the 15% patterned default.
- Peel-and-stick (removable) wallpaper: roll sizes and usable coverage for peel-and-stick products commonly differ from the standard 56 sq ft double-roll default this calculator assumes, and repositioning during installation can consume more material than a traditional pasted, no-reposition hang. Always enter the coverage figure printed on your specific peel-and-stick product rather than the default.
- Rooms being papered by a first-time installer rather than a professional: the waste allowances in this calculator reflect fairly efficient cutting; a first attempt at wallpapering, with more trial cuts and the occasional misaligned strip that gets discarded, commonly runs higher than either default. If this is your first wallpaper project, consider ordering one roll beyond this calculator's result as a learning-curve buffer.
FAQ
What's a 'double roll' and why does it matter?
A double roll is the standard US retail unit for wallpaper — two single rolls bonded together and sold as one package, typically covering about 56 sq ft of usable wall area. Most US wallpaper is priced and sold this way, so this calculator's default coverage figure assumes a double roll. If you're buying single rolls or an imported European roll (a different standard size), adjust the coverage rate in Advanced settings to match what's printed on your specific product's label.
Why does patterned wallpaper need more extra material than plain?
Patterned wallpaper has a repeat — a design element that must line up across adjoining strips. Every time you cut a new strip, you typically have to shift the cut point to keep the pattern aligned with the strip next to it, which wastes more material than a plain, non-repeating paper where any cut point works. Large-scale repeats (over about 20 inches) waste more than small ones, so this calculator's 15% patterned default is a reasonable mid-range figure — a very large repeat may need more.
Does the calculator subtract doors and windows the same way as the paint calculator?
Yes — this uses the same standard opening-size assumptions (about 17 sq ft per door, 15.5 sq ft per window) as BuildyWork's paint calculator, since wallpaper and paint both cover the same paintable/paperable wall surface. If your room has an unusually large window or double doors, the calculator will slightly overestimate rolls needed, which is the safer direction to be wrong in.
Can I wallpaper just one accent wall?
Yes — measure only that wall's length and set the room's other dimension (width) to a very small value, or better, treat the accent wall as its own rectangle: enter its length as the wall's width and 0 as room width isn't supported, so instead run the calculator with length = accent wall width and width = 0.01 to approximate a single-wall area, then round the result up as usual. A future version may add a dedicated single-wall mode.
What if I'm papering a ceiling too?
This calculator only computes wall area, not ceiling area. Ceilings are measured and ordered separately — measure the ceiling's length × width, divide by your roll's usable coverage, and add that to your wall total before applying a single combined waste allowance, since ceiling papering (increasingly rare but still done in period-style rooms) typically has similar trim waste to walls.
Should I round up or buy an extra roll on top of the rounded result?
This calculator already rounds up to the next whole roll and applies a waste allowance on top of your raw wall area, so the result already includes a buffer. For most rooms that's sufficient. Consider one additional roll only if you're papering an oddly shaped room (heavy alcoves, a chimney breast, sloped sections) where real-world cutting waste tends to run higher than a simple rectangular model predicts.
Why is my result different from what the wallpaper store quoted me?
Store estimators sometimes use a flat percentage waste allowance regardless of pattern type, or assume a different roll size (single roll vs. double roll, US vs. European format) than the product you're actually buying. Always confirm your chosen product's exact roll coverage and repeat size against the manufacturer's own label, and adjust this calculator's Advanced settings to match — the store's number and this calculator's number should converge once both use the same inputs.
Does wallpaper thickness or material (vinyl, grasscloth, non-woven) change the amount I need?
Not directly — roll coverage area is driven by the roll's physical dimensions, not its material, so a vinyl and a non-woven roll of the same size cover the same area. Material does affect installation difficulty and how forgiving mismatched cuts are (grasscloth, for instance, has natural variation that makes small mismatches less noticeable), but it doesn't change the quantity math this calculator performs.
Can I switch between imperial and metric partway through?
Yes — the unit toggle at the top of the calculator converts every field you've already entered, so you won't lose your measurements. Internally the tool always computes from the same canonical values regardless of which unit is currently displayed, so switching back and forth doesn't introduce any rounding error into your result.
What's the difference between this and the paint calculator?
Both start from the same wall-area math (perimeter × height, minus openings), but wallpaper is sold in discrete rolls with a repeat-driven waste allowance, while paint is sold in cans divided by a coverage-rate-per-coat calculation. If you're deciding between painting and papering a room, run both calculators with the same dimensions to compare quantities and shopping lists side by side.
Why does this calculator default to 10% waste for plain paper when I've seen guides suggest as little as 5%?
Industry installation guides generally cite a 5-10% range for plain, non-repeating wallpaper, and this calculator uses the top of that range (10%) as a conservative default so first-time buyers are less likely to run short. If you're an experienced installer confident in tighter cutting and have measured the room precisely, you can lower the waste allowance in Advanced settings toward 5% — just recognize that leaves less room for measurement error or an unexpected extra cut.
Do I need extra wallpaper for a stairwell wall?
Yes, more than the flat wall area suggests. A raked (angled) stairwell wall has more actual surface area than its footprint implies, and the angled top edge produces more angled, less reusable offcuts than a standard rectangular wall. Measure the stairwell wall's actual height at its tallest point, treat it as its own area calculation, and budget a higher waste allowance than the flat-wall default — see the edge-case guidance below.
Can I mix leftover rolls from two different orders if I run short?
Only if they share the same lot or run number — printed on most wallpaper rolls' packaging or spine label. Wallpaper dye lots can shift subtly in color between production runs even for the identical SKU, and a mismatched lot is usually very visible once hung, especially under raking light. If your leftover rolls don't share a lot number with your new order, treat them as unusable for the same wall and order fresh instead.
Does hanging wallpaper horizontally instead of vertically change the roll count?
It can, depending on the pattern repeat and how the roll's width divides into your wall height versus wall length. Horizontal hanging is uncommon and typically increases waste because most rolls are manufactured and repeat-matched assuming vertical strips running floor to ceiling. If you're planning a horizontal or non-standard hang, consult the manufacturer's specific installation guide rather than relying on this calculator's standard vertical-strip assumption.
Why does this calculator use 56 sq ft as the double-roll coverage figure instead of the roll's total printed area?
Manufacturers typically print a roll's gross area (the full uncut material) on the packaging, but that figure overstates what actually ends up on the wall once trimming, pattern-matching, and edge waste are accounted for. The 56 sq ft default already reflects usable coverage after typical trim loss, following York Wallcoverings' and comparable manufacturer guidance — if you separately apply this calculator's waste allowance on top of a gross-area figure instead of a usable-coverage figure, you risk double-counting some of the same waste and overbuying.
How much does professional installation labor typically add to a wallpaper project's cost, roughly?
This calculator estimates material quantity only, not labor cost, and labor rates vary widely by region and installer. As a rule of thumb for budgeting purposes, professional wallpaper installation labor is commonly priced per roll or per square foot and can be a comparable or larger cost than the material itself, especially for patterned or difficult-to-match papers — get a quote from a local installer once you know your roll count from this calculator, rather than assuming material cost dominates the budget.
Is peel-and-stick (removable) wallpaper measured the same way as traditional pasted wallpaper?
The area math is the same, but peel-and-stick products are frequently sold in different roll sizes than traditional double rolls, and repositioning during installation (a common advantage of peel-and-stick) can use up material differently than a first-try, no-reposition pasted install. Check your specific peel-and-stick product's stated coverage per roll rather than assuming the 56 sq ft double-roll default applies, since peel-and-stick rolls often cover less.