Wallpaper calculator
The calculator needs JavaScript. The worked example, formula and figures below show exactly how it works, so you can do the sum yourself. A guide, not advice. Check your supplier's or maker's figures before ordering.
Short answer
Work out how many rolls of wallpaper to buy, drop by drop. Enter your measurements below; every figure we start from is shown and you can change it.
Worked example
| You enter | Value |
|---|---|
| Total width of walls to paper | 14 m |
| Wall height | 2.4 m |
| Full-height openings to leave out | 0 m |
| Pattern repeat | 0 m |
| Roll length | 10.05 m |
| Roll width | 0.53 m |
| Trim allowance per drop | 0.1 m |
| Spare rolls | 0 |
Order: 7 rolls
| Result | Value |
|---|---|
| Rolls | 7 |
| Drops (strips) | 27 |
| Drops per roll | 4 |
| Length of each drop | 2.5 m |
Show the working
- Drop: 2.4 m + 0.1 m trim = 2.5 m
- Drops per roll: 10.05 m ÷ 2.5 m = 4 (rounded down)
- Drops: 14 m ÷ 0.53 m = 26.42, rounded up to 27
- Rolls: 27 ÷ 4, rounded up = 7
How it works
- Drop = wall height + trim, rounded up to a whole number of pattern repeats
- Drops per roll = roll length ÷ drop, rounded down
- Drops = (wall width − full-height openings) ÷ roll width, rounded up
- Rolls = drops ÷ drops per roll, rounded up, plus any spare rolls
Buy rolls from one batch: colours can vary between batches.
Half-drop patterns: follow the maker's guidance.
Our default (adjustable)
These are typical planning figures and our own allowances, not facts about your product. Change any of them in the calculator to match your bag, pack or tin.
| Figure | Our default (adjustable) | Kind | Source |
|---|---|---|---|
| Roll length | 10.05 m | Common UK size Not yet checked against the source | Roll size quoted by trade calculators (checked 19 October 2026) Standard UK roll. |
| Roll width | 0.53 m | Common UK size Not yet checked against the source | Roll size quoted by trade calculators (checked 19 October 2026) Sources quote 0.52 or 0.53 m wide; check the label. |
| Trim allowance per drop | 0.1 m per drop | Our assumption Not yet checked against the source | Our choice: change it to suit your job Trimming allowance at top and bottom. |
| Spare rolls | 0 rolls | Our assumption Not yet checked against the source | Our choice: change it to suit your job Add a spare if the pattern is hard to match later. |
FAQs
Guides
How many rolls of wallpaper do I need?
Work out drops per roll, allow for the pattern repeat and buy from one batch. How lining paper changes the sum.