Wallpaper Calculator
Assumes a standard 10 m × 52 cm roll. Large pattern repeats need more.
How many rolls of wallpaper do I need?
Enter the room dimensions and the calculator estimates the rolls, based on a standard UK roll of 10 m by 52 cm, which yields roughly five usable square metres once you allow for trimming, plus 10% for pattern matching. The pattern repeat is the wild card: a large repeat wastes more at every drop, so a boldly patterned paper can need noticeably more than a plain one.
Always buy every roll from the same batch number so the colour matches exactly, and keep one spare. Measure wall by wall for an awkward room rather than treating it as one big rectangle, and do not deduct small windows, treat them as pattern insurance.
Frequently asked questions
Is the wallpaper calculator free?
Yes. It is completely free, with no sign-up and nothing to install. It runs entirely in your browser.
How accurate is it?
It gives a reliable estimate for ordering based on standard UK figures, but real quantities vary with ground conditions, wastage and how materials settle. Always add a margin and confirm with your supplier before buying.