Wallpaper Calculator — How Many Rolls Do I Need?

The standard UK wallpaper roll is 10.05m long × 0.53m wide, giving a coverage area of approximately 5.3 m². Some manufacturers offer wider rolls at 0.70m width. European rolls and designer brands like Farrow & Ball may differ slightly — always check the roll dimensions on the packaging before ordering.

Pattern repeat means each strip of wallpaper must be aligned with the adjacent strip. To match the pattern, every drop is cut to the next whole multiple of the repeat above the wall height (plus trim), so a longer repeat leaves a bigger offcut and gives fewer usable drops per roll. Enter the exact vertical repeat in millimetres from the roll label and the calculator rounds the cut length up to the next repeat automatically. On a 2.4m wall and a standard 10.05m roll, plain paper or a stripe (no vertical repeat to match) gives 4 drops per roll, while a small patterned repeat of around 180mm gives 3. Because the cut jumps to the next whole repeat, the exact figure depends on the precise repeat — let the calculator work it out from the value you enter rather than relying on a rule of thumb.

Yes — always round up. You cannot buy half rolls, and it is essential to have spare wallpaper from the same batch in case of mistakes, damage, or future repairs. We recommend buying at least one extra roll beyond the calculated amount. Wallpaper dye lots can vary, so buying all your rolls together ensures consistent colour. If you are painting other rooms instead, try our Paint Coverage Calculator.

By default, no. The standard trade estimate papers the full room perimeter, because you still hang full-height drops alongside a door and above and below a window — you only recover small offcuts, so deducting the whole opening width tends to under-order. Our calculator leaves openings in by default and gives you an optional 'Deduct openings' switch for genuinely wide full-height openings such as patio doors. Screwfix and Farrow & Ball both estimate on the full perimeter, then add an extra roll for safety.

Yes, exactly. Enter the room's overall length and overall width as if it were a full rectangle. A notch cut from a corner does not change the perimeter, because the two walls of the notch line up with the wall sections they replace, so an L-shaped room needs exactly the same number of drops as its bounding rectangle. A chimney breast is different: the wall steps in and out around it, adding its two short return sides to the perimeter. Allow for one by adding the depth of the breast to your room length measurement (the calculator doubles the length, which covers both returns), and expect a little extra pattern-matching care at its two external corners.

It depends on the pack size and mix strength. Solvite All Purpose paste, for example, is sold in packs rated for roughly 5, 7.5, 10 or more rolls — a common box covers around 7 to 10 standard rolls when mixed at the normal strength. Heavy, embossed or vinyl papers need a thicker mix, which covers fewer rolls per pack. Always check the pack and follow the manufacturer's mixing ratio for the wallpaper type you are hanging.