How many rolls of wallpaper do I need?
The honest answer is: it depends on your pattern repeat, not just your wall area. A plain paper and a large-repeat floral covering the exact same wall can need a very different number of rolls, because with a repeat you have to trim each strip to line the pattern up — and that offcut is waste. RollRight is built around the way professional decorators actually estimate: the strip method.
The strip method, step by step
- Cut length = wall height + trim allowance, rounded up to the next whole pattern repeat (half-drop adds an extra half repeat on alternate strips).
- Strips per roll = roll length ÷ cut length, rounded down.
- Strips needed = papering width ÷ roll width, rounded up, minus strips saved by full-height doors.
- Rolls = strips needed ÷ strips per roll, rounded up, plus a spare margin.
Why area-only calculators are wrong
Dividing total wall area by "square metres per roll" ignores the fact that a roll only yields whole strips. If your cut length is 2.6 m and the roll is 10 m, you get 3 usable strips (7.8 m) and 2.2 m is scrap. Area maths would tell you that 2.2 m is still usable — it isn't. That's how people end up one roll short on a Sunday with the shop shut.
Standard wallpaper roll sizes
Most UK and European wallpaper rolls are 53 cm wide × 10 m long (about 5.3 m²). US rolls are commonly sold as double rolls around 27 in wide × 27 ft long. Always check the label and enter the real figures above — RollRight works in both metric and imperial.
Frequently asked questions
How does the pattern repeat change how much wallpaper I need?
Every strip must be cut so the pattern lines up with the strip beside it. That means rounding each strip's length up to a whole repeat, so a bigger repeat means more waste per strip and fewer usable strips per roll. A 64 cm repeat can cost you a whole extra roll versus a plain paper on the same wall — which is exactly why this calculator asks for it.
What is the difference between straight match and half-drop match?
With a straight match the pattern sits at the same height on every strip. With a half-drop match every other strip is shifted down by half the repeat to create a diagonal flow, so alternate strips need an extra half-repeat of length — more waste. Choose the match type from the label and RollRight adjusts the maths automatically.
Should I buy extra wallpaper?
Yes. We add a spare margin by default for trimming errors, damaged strips and future repairs. Buy all your rolls in one go and check they share the same batch number — different batches can vary slightly in colour.
Does it account for doors and windows?
Full-height doors let you save whole strips, so we deduct for them conservatively. Standard windows rarely save a full strip (you still paper above and below), so we don't over-deduct — being slightly generous here is what stops you running short.
Is my data sent anywhere?
No. RollRight runs entirely in your browser. There are no accounts, no tracking and no network calls — you can turn your Wi-Fi off and it still works.