Find out exactly how many rolls you need — enter room dimensions, roll size, pattern repeat, and openings for an instant result.
Shorter side of the room
Longer side of the room
Floor to ceiling (typical: 2.4 m / 8 ft)
Standard EU/UK: 0.53 m (53 cm)
Standard EU/UK roll: 10 m
Found on the wallpaper label — enter 0 for plain/textured wallpaper
A wallpaper calculator removes the guesswork from buying wallpaper. Instead of making a rough guess and either running short mid-project or paying for excess rolls you'll never use, you enter your room's exact measurements and get an accurate roll count instantly.
The calculator works by computing the total perimeterof your room, dividing by the roll width to find the total number of vertical strips needed, accounting for waste caused by pattern repeats, subtracting strips saved by windows and doors, and then dividing by the number of usable strips per roll. The result tells you exactly how many rolls to order before you set foot in the shop.
Getting this right is more important than most people expect. Wallpaper is sold in batches, and the dye lot — the specific batch number printed on the label — can vary slightly in colour from one production run to the next. If you run short and need to buy a second order, there's a real risk of a visible colour difference on the wall. Buying enough from a single batch the first time avoids this problem entirely.
This tool supports both metric units (meters, standard in Europe and the UK) and imperial units (feet for room dimensions, inches for roll width, feet for roll length, as commonly found in the US). It handles any room size, any roll format, and lets you specify a pattern repeat for accurate waste calculation.
The pattern repeat is the critical variable that catches many people off guard. A 0.64 m pattern repeat on a 2.4 m wall means the effective strip length jumps to 2.56 m (the next whole multiple of 0.64 m above 2.4 m), leaving 0.16 m of waste per strip. On a roll of 10 m, that reduces usable strips from 4 to 3 — increasing your roll count by 33%.
Approximate roll counts for a standard EU/UK roll (0.53 m × 10 m), plain wallpaper (no repeat), 2.4 m ceilings, one door (0.9 m wide) and one window (1.2 m wide):
| Room type | Dimensions | Perimeter | Rolls needed |
|---|---|---|---|
| Small bedroom | 3.0 m × 3.5 m | 13.0 m | ~9 rolls |
| Standard bedroom | 3.5 m × 4.5 m | 16.0 m | ~10 rolls |
| Master bedroom | 4.0 m × 5.0 m | 18.0 m | ~11 rolls |
| Small living room | 4.0 m × 5.0 m | 18.0 m | ~11 rolls |
| Large living room | 5.0 m × 7.0 m | 24.0 m | ~14 rolls |
| Kitchen | 3.0 m × 4.0 m | 14.0 m | ~9 rolls |
| Bathroom | 2.0 m × 3.0 m | 10.0 m | ~7 rolls |
| Hallway (straight) | 1.2 m × 5.0 m | 12.4 m | ~8 rolls |
Values are approximate for plain wallpaper. Patterned wallpaper with a large repeat will need significantly more. Use the calculator above for your exact dimensions and roll format.
Emma is wallpapering her 3.8 m × 4.2 m bedroom with 2.4 m ceilings using a plain linen-effect wallpaper (0.53 m × 10 m rolls, 0 pattern repeat). She has one window (1.2 m wide) and one door (0.9 m wide).
Perimeter: 2 × (3.8 + 4.2) = 16.0 m. Strips: ceil(16.0 ÷ 0.53) = 31. Strips per roll: floor(10 ÷ 2.4) = 4. Deduct window: floor(1.2 ÷ 0.53) = 2 strips. Deduct door: floor(0.9 ÷ 0.53) = 1 strip. Net strips: 31 − 2 − 1 = 28. Rolls: ceil(28 ÷ 4) = 7 rolls. With +10%: 8 rolls.
James is papering his 5.0 m × 6.0 m living room (2.4 m ceilings) with a bold botanical print (0.53 m × 10 m, 0.64 m pattern repeat). Two windows (1.4 m wide each), one door (0.9 m wide).
Perimeter: 22.0 m. Total strips: ceil(22.0 ÷ 0.53) = 42. Effective height: ceil(2.4 ÷ 0.64) × 0.64 = 4 × 0.64 = 2.56 m. Strips per roll: floor(10 ÷ 2.56) = 3. Deduct 2 windows: 2 × floor(1.4 ÷ 0.53) = 2 × 2 = 4 strips. Deduct door: 1. Net strips: 42 − 4 − 1 = 37. Rolls: ceil(37 ÷ 3) = 13 rolls. With +10%: 15 rolls.
Maria is papering her 7 ft × 9 ft bathroom (8 ft ceilings) using a US double roll (21 in wide × 33 ft long). One window (24 in wide), one door (32 in wide). No pattern repeat.
Roll width: 21 in = 1.75 ft. Perimeter: 2 × (7 + 9) = 32 ft. Total strips: ceil(32 ÷ 1.75) = 19. Strips per roll: floor(33 ÷ 8) = 4. Deduct window: floor(2 ÷ 1.75) = 1. Deduct door: floor(2.67 ÷ 1.75) = 1. Net strips: 19 − 1 − 1 = 17. Rolls: ceil(17 ÷ 4) = 5 rolls. With +10%: 6 rolls.
| Pattern type | Waste per strip | Notes |
|---|---|---|
| Plain / texture (no repeat) | Minimal (trim only) | Easiest to hang, least waste |
| Random match | None | Paste any strip next to any other — no alignment needed |
| Straight match (set match) | Up to 1 full repeat | Pattern at same height on every strip — half-step waste |
| Half-drop match | Up to 1 full repeat | Pattern drops by half repeat on alternate strips — slightly more waste |
| Large repeat (>0.5 m) | Up to 1 full repeat per strip | Can increase roll count by 20–40% — plan carefully |
Calculate the room perimeter (2 × width + 2 × length), divide by the roll width to get the total strip count, deduct strips saved by large openings, divide by strips per roll (roll length ÷ effective strip height), and round up. A typical 4 m × 4 m room with standard 0.53 m × 10 m rolls and no repeat needs around 8–9 rolls. Our calculator does all of this automatically.
A pattern repeat is the vertical distance after which the wallpaper design repeats. To align patterns between adjacent strips, you must cut each strip at the start of the repeat, creating waste equal to up to one full repeat per strip. A large 0.64 m repeat on a 2.4 m wall means cutting strips to 2.56 m (the next multiple of 0.64 above 2.4 m), leaving 0.16 m waste. This reduces strips per roll from 4 to 3, increasing the total roll count significantly.
In the UK and Europe, the standard is 0.53 m (53 cm) wide × 10 m long. In the US, wallpaper is typically sold in double rolls: 27 in × 27 ft or 21 in × 33 ft. Always verify the dimensions printed on your specific packaging before calculating, as premium and designer wallpapers sometimes use different roll sizes.
You can deduct openings that take up full strips from edge to edge. The calculator deducts the number of complete strips that are covered by each window or door opening. Strips that run alongside an opening but also cover wall area are not deducted — you still need those strips. This approach errs slightly on the side of caution, which is correct.
Always add at least 10% — that's one extra roll for every 10 calculated. For patterned wallpaper with a large repeat (over 0.5 m), budget 15–20% extra. Buy all rolls in a single order, verify the batch numbers on every roll match, and keep at least one sealed roll for future repairs. Wallpaper patterns get discontinued, so a future batch match may be impossible.
Treat each distinct wall section separately. Measure the width and height of each section, calculate strips needed for each, and add the totals. Alcoves and chimney breasts each need their own strip counts. Then sum all sections to find the total strips and convert to rolls. Our calculator works best for standard rectangular rooms — for complex shapes, run it per section and add up.
Paste-the-wall (non-woven) wallpaper: you paste the wall surface, then hang the dry paper. It is much easier for beginners — strips do not expand when wet, can be repositioned briefly, and trim cleanly with a sharp knife. Paste-the-paper (traditional) wallpaper: you paste the back of the paper and let it soak before hanging. It expands when wet and needs careful handling. The roll count calculation is the same for both types.