Wallpaper Calculator: How Many Rolls of Wallpaper Do I Need?

Buy wallpaper by the strip, not the wall. This calculator counts how many full-height drops your room needs, how many drops you get from a roll once trimming is allowed, and turns that into a roll count. The number most people get wrong is the pattern repeat: a large repeat forces you to waste part of every drop to line the design up, which can add a whole roll or two to the job.

Standard British wallpaper rolls are 10.05 m long and 53 cm wide, so the defaults suit most papers, but always check the label because wide-width and designer rolls differ. We add 10 cm to every drop for trimming top and bottom, and we do not deduct doors or windows: the offcuts around openings rarely give you a usable full-height drop, so counting them keeps you from running short. Order all your rolls in one go and check the batch number matches, as colours can shift between print runs.