How it works

What a wallpaper roll calculator needs before the answer is worth trusting.

Start with wall width and ceiling height, subtract the openings, then compare the net wall area against the roll size and the pattern repeat.

1. Measure the room

Use one wall at a time when the room changes height. Older rooms can drift more than the paint line suggests.

Deduct big openings, but do not get too aggressive. Wallpaper still needs trimming room around frames and corners.

A long repeat can turn a safe-looking roll count into a short order if you ignore match waste.

If the room lands between two counts, round up and keep all rolls in the same lot for color consistency.