🔧 EasyBuildCalc

Free Wallpaper Calculator

Calculate how many wallpaper rolls you need for any room. Deducts doors and windows, adjusts for waste, and supports US and Euro roll sizes.

Wallpaper Calculator

Wall Area

435 sq ft

486 − 51 openings

With Waste

500 sq ft

+15%

Rolls Needed

18

28 sq ft each

Est. Cost

$810

at $45/roll

Pattern repeat tip: Wallpaper with a pattern repeat requires additional waste — use 20–25% waste instead of 15% to account for matching drops between strips.

Wallpaper Roll Sizes & Coverage

Roll TypeWidthLengthCoverage
US Single Roll20.5"16.5 ft~28 sq ft
US Double Roll20.5"33 ft~57 sq ft
Euro Double Roll20.5"33 ft~56 sq ft
Wide Commercial Roll27"15 yd~101 sq ft
Buy from the same dye lot: Wallpaper color can vary between production batches. Always buy all rolls for a room at once from the same lot number — printed on the roll label. If you run short and reorder, the new lot may not match exactly.

Frequently Asked Questions

How many rolls of wallpaper do I need?+

Calculate gross wall area (perimeter × height), subtract 21 sq ft per door and 15 sq ft per window, add 15% waste, then divide by your roll's sq ft coverage. A US double roll covers ~57 sq ft. A 12×15 ft room at 9 ft with 1 door and 2 windows needs roughly 8–9 double rolls.

How much extra wallpaper for pattern matching?+

Plain textures and stripes: 10–15% extra. Wallpapers with a 3–6 inch pattern repeat: 15–20%. Large-repeat designs (12+ inches): 25–30%. The larger the repeat, the more you waste on matching adjacent strips. Our calculator defaults to 15% — increase it manually for patterned paper.

How many sq ft does a double roll cover?+

A US or Euro double roll covers 56–57 sq ft. But usable coverage is often less after trimming edges and matching patterns — budget for 50–54 sq ft effective coverage per double roll for plain paper, less for patterned. Always check the label; coverage is printed on every roll.

How much does it cost to wallpaper a room?+

Budget wallpaper: $15–30 per double roll. Mid-range: $30–80. Designer/specialty: $80–300+. A standard 12×15 ft room needs 8–10 double rolls. Add $200–600 for professional installation. DIY installation with pre-pasted wallpaper is accessible for first-timers on smooth walls.