How this calculator works
It measures your wall area (room perimeter × wall height) and adds 15% for pattern matching and trimming, then divides by the usable coverage of one roll.
Worked example — a 12 ft × 12 ft room, 8 ft walls, single rolls:
Perimeter 48 × 8 = 384 sq ft × 1.15 = 442 ÷ 25 = 18 rolls.
Perimeter 48 × 8 = 384 sq ft × 1.15 = 442 ÷ 25 = 18 rolls.
Patterns need more
Big repeating patterns waste more at each seam. For a large pattern repeat, bump your order up by another roll or two.
Frequently asked questions
How much wallpaper do I need for one room?
Measure the wall area and divide by the roll’s usable coverage — most single rolls cover about 25 sq ft after trimming.
Should I buy single or double rolls?
Double rolls have fewer seams and less waste on tall walls, but single rolls are easier to handle.