Wallpaper Calculator
Instantly estimate how many rolls of wallpaper you need for your room. Accounts for wall dimensions, roll size, pattern repeat, and trimming waste.
Estimate Your Wallpaper Rolls
Enter your room dimensions and wallpaper roll specifications below to get an accurate estimate of the number of rolls required.
Roll Estimator
Calculate exactly how much wallpaper to buy for your project.
How it Works
Understanding the wallpaper calculation
Calculate Drops
We divide your total wall width by the roll width to determine how many vertical strips (drops) are needed to cover the space.
Factor in Pattern
The calculator adds your pattern repeat and a 10cm trimming allowance to the wall height to find the true length needed per drop.
Drops per Roll
We divide the total roll length by the required drop length to see how many usable strips you can get from a single roll.
Total Rolls
Finally, we divide the total drops needed by the drops per roll, rounding up to ensure you have enough material to complete the job.
Wallpaper Measurement Tips
Helpful guidelines for measuring your room and understanding standard wallpaper specifications.
| Measurement Type | Standard / Guideline | Notes |
|---|---|---|
| Standard Roll Size (UK) | 10.05m long × 52cm wide | The most common size for mainstream wallpaper brands. |
| Wide Roll Size | 10m long × 68-70cm wide | Often used for premium, textured, or non-woven wallpapers. |
| Trimming Allowance | +10cm per drop | Added to wall height to allow for cutting at the ceiling and skirting board. |
| Doors & Windows | Do not deduct | Offcuts are rarely usable elsewhere due to pattern matching. Calculate full wall width. |
| Pattern Match Types | Straight, Drop, or Random | ‘Random’ means 0cm repeat. ‘Drop’ means half the repeat is lost per strip. |
| Batch Numbers | Must match | Always ensure all rolls purchased share the same batch number to avoid colour variation. |
Wallpaper Calculator FAQ
Answers to the most frequently asked questions about measuring for wallpaper, pattern repeats, and buying extras.
To calculate wallpaper needed, measure the total width and height of the walls. Divide the total width by the width of the wallpaper roll to find the number of ‘drops’ (strips) needed. Then, divide the roll length by the wall height (plus pattern repeat and a 10cm trimming allowance) to find how many drops you get per roll. Finally, divide the total drops needed by the drops per roll, rounding up to the nearest whole number.
Pattern repeat is the vertical distance between where a design motif begins and where it repeats again. It matters because you must start each new strip of wallpaper at the same point in the pattern to ensure it aligns seamlessly. This matching process creates offcut waste, which is why our calculator factors it in to ensure you buy enough rolls.
Generally, no. It is best practice to calculate wallpaper based on the total continuous wall width. Offcuts from above doors or windows are rarely long enough to be used above or below other openings, especially when pattern matching is required. It is always safer to overestimate slightly and use the calculator’s result as a solid baseline.
The most common standard wallpaper roll size in the UK is 10.05 metres long and 52 centimetres (0.52m) wide. However, some premium, textured, or non-woven wallpapers may come in wide-roll dimensions, such as 10m x 70cm. Always check the label on your specific roll before using the calculator.