Wallpaper Calculator
Enter room perimeter and room height – get the exact number of rolls instantly
- Updated
Room perimeter = 2 × (length + width) of the room.
Combined, in metres – whole strips are saved there. Do not subtract normal windows: the pieces above and below still need paper.
Pattern (repeat)no pattern
Length after which the pattern repeats; 0 = paper without pattern
Roll size0.53 × 10.05 m, trim allowance 10 cm
Standard size 0.53 × 10.05 m – roll area: 5.33 m²
Each strip is cut a little longer than the room height and trimmed at ceiling and skirting. 10 cm (5 cm top and bottom) is our assumption, not a standard – add the pattern repeat for patterned wallpaper.
Rolls needed
13rolls
13For a 20 m perimeter at 2.5 m room height you need 38 strips. With trim allowance each strip is 2.6 m long, one roll gives 3 – that makes 13 rolls.
- Strips per roll
- 3
- Total strips
- 38
How this was calculated
Only whole strips of room height plus trim allowance count per roll; strips and rolls are rounded up.
What you can do
Keep 1–2 spare rolls from the same batch
The batch number ensures identical colour tones – important for large-scale patterns or complaints.
RZ-26 · headon.pro
Calculating wallpaper correctly: method and practice
Strips, rolls and roll length – how the calculation works
Calculating wallpaper rolls follows a clear scheme: first, you work out how many wallpaper strips fit on one roll. Every strip needs some extra length so it can be trimmed cleanly at ceiling and skirting – the calculator assumes 10 cm per strip (adjustable). A standard roll with a 10.05 m length therefore gives three strips of 2.60 m at a 2.50 m room height (⌊10.05 ÷ 2.60⌋ = 3); four would fit on paper, but would leave barely 1 cm per strip for trimming. Then the total number of strips needed is calculated: room perimeter divided by roll width, rounded up. At a 20 m perimeter and 0.53 m width, that is 38 strips (⌈20 ÷ 0.53⌉). 38 ÷ 3 = 12.7 → rounded up to 13 rolls.
Standard roll dimensions in Germany: Most ceiling and wall wallpapers are sold in 0.53 m width and 10.05 m length. This is the DIN standard size for the European market. Older rolls often had 10.0 m, modern non-woven wallpapers come at 10.05 m – a small difference that can still affect the number of rolls needed. Always check the exact roll length on the product packaging.
Non-woven vs. paper wallpaper: Non-woven wallpaper has been the standard in Germany since around 2010. The key difference: with paper wallpaper, the paper is soaked and needs about 5–10 minutes of soaking time. With non-woven wallpaper, the paste is applied to the wall and the wallpaper is hung dry. Non-woven wallpaper is more dimensionally stable and does not warp when pasted – which makes it much easier to work with. Both types share the same roll format.
Pattern and repeat: Wallpaper without a pattern (repeat 0) can be joined seamlessly – waste only comes from trimming to room height. With patterned wallpaper (e.g. a 30 cm or 64 cm repeat), each strip must be offset so the pattern lines up seamlessly. The larger the repeat, the more waste. For wallpaper with a repeat greater than 25 cm, professionals recommend an extra 1–2 rolls of reserve beyond the calculation.
Wallpaper categories and their characteristics
Key wallpaper types at a glance
- Non-woven wallpaper
- Today’s standard; hung dry, paste applied to the wall; dimensionally stable
- Woodchip wallpaper
- Inexpensive; needs soaking; painted afterwards; often 53 cm wide
- Textured wallpaper
- Embossed surface; often non-woven; for living rooms and accent walls
- Photo wallpaper
- Usually ordered in cm; no standard format; needs its own calculation
- Fibreglass wallpaper
- Especially durable; for heavily used surfaces; 50–100 cm wide
- Natural fibre wallpaper
- Jute, sisal, seagrass; eco-friendly; higher price; 92–100 cm wide
Calculation examples
- Strips per roll (⌊10.05 ÷ 2.60⌋, incl. 10 cm trim allowance)
- 3
- Total strips (⌈20 ÷ 0.53⌉)
- 38
- Rolls (⌈38 ÷ 3⌉)
- 13
- Strips per roll (⌊10.05 ÷ 2.70⌋, incl. 10 cm trim allowance)
- 3
- Total strips (⌈14 ÷ 0.53⌉)
- 27
- Rolls (⌈27 ÷ 3⌉)
- 9
Frequently asked questions about the wallpaper calculator
Roll dimensions, patterns and hanging tips
What is the size of a standard wallpaper roll?
The most common wallpaper size in Germany is 0.53 m wide and 10.05 m long – giving a total area of about 5.33 m² per roll. These dimensions have become the standard and apply to both non-woven and paper wallpaper. Specialty products such as woodchip, fibreglass wallpaper or wide designer wallpapers can differ – always check the product details before buying.
How do I calculate the room perimeter?
The room perimeter is the sum of all wall lengths. For a rectangular room: perimeter = 2 × (length + width). For a room 5 m long and 4 m wide, that is 2 × (5 + 4) = 18 m. Measure each wall individually if the room is irregular. The wallpaper calculator does not deduct doors and windows separately – this provides the reserve needed for trimming waste and pattern matching.
Why aren’t doors and windows deducted?
Hanging wallpaper produces waste from pattern matching and from trimming the strips. The areas of doors and windows serve as a natural reserve for this waste. If doors and windows were deducted, rolls would frequently run short in practice. Professional decorators calculate without any deduction by default and buy 1–2 extra rolls if needed.
What does pattern repeat mean and how much extra do I need?
For wallpaper with a repeat (a recurring pattern), each new strip must be positioned so the pattern lines up. With a 30 cm pattern repeat, up to 30 cm of material can be lost per strip. For wallpaper with a large repeat, you should budget an extra 15–20%. Plain wallpaper with no pattern (repeat 0) has no such extra consumption.
Can I ignore the batch number on wallpaper?
No. The batch number (also called a lot or run number) indicates which production batch the wallpaper came from. Even with the same colour, different batches can vary slightly – visible on the wall as a subtle colour difference. Always buy all the rolls you need from the same batch. When in doubt, buy 1–2 extra rolls and keep them unopened.