Wallpaper Calculator
Enter your wall area and pattern repeat size to get a roll count based on real usable coverage, not the roll's nominal size.
Rolls needed
11 rolls
Usable coverage per roll
30 sq ft
Waste applied
10%
At the default (300 sq ft, no pattern repeat) that's 11 rolls.
How it's calculated
The calculator adds a waste percentage set by your pattern's repeat size -- no or small repeat, a moderate repeat under 18 inches, or a large repeat 18 inches or more -- to your wall area, then divides by the usable coverage per roll and rounds up to a whole roll.
Keep going
- Deciding between wallpaper and paint for the same room? The paint calculator prices out the same wall area in gallons. Paint Calculator
- Get an accurate wall area first if the room has an alcove, bay window, or other non-rectangular wall to account for. Square Footage Calculator
Frequently Asked Questions
Why does this use 30 sq ft per roll instead of the roll's printed size?
A US single roll is commonly rated around 56 sq ft nominal, but published wallpaper-estimating guides count roughly 30 sq ft of usable wall coverage per roll once trimming and basic matching are accounted for. This calculator uses that usable figure so the roll count reflects what you'll actually get on the wall.
What counts as a large pattern repeat?
A repeat under about 18 inches is treated as moderate here; 18 inches or more is treated as large. A bigger repeat means more of each drop gets trimmed away to keep the pattern aligned at every seam, which is why it adds more waste.
Do I need extra rolls for a feature wall?
A single feature wall usually needs proportionally more waste than a full room, since there's less flexibility to shift the pattern around corners -- consider using the moderate or large repeat tier even for a small/no-repeat pattern on a single standout wall.
What's the difference between a single roll and a double roll?
Some wallpaper is sold in "double rolls" -- two single rolls bundled together, covering roughly twice the area per package. This calculator's roll count is in single-roll units; divide by two if you're buying double rolls.
Should a first-time DIY job buy extra rolls?
Yes, generally -- a first hang commonly has more misaligned or wasted cuts than an experienced installer's job. Buying one extra roll beyond this calculator's result is common practical advice, especially with a large pattern repeat.