Wallpaper calculator
Work out how many rolls of wallpaper to buy. Enter the room or each wall, the height, and the roll size and pattern repeat from the label, and see how many drops you need, how many you get from each roll, and the rolls to buy.
Walls
The width of each wall you're papering, in metres. For a feature wall, add just that one.
From the top of the skirting board to the ceiling or coving, at the highest point.
Wallpaper
Pattern match
The label shows the match and repeat. Free match (plain or textured) wastes least; a half-drop match wastes most.
Updates as you type. Runs in your browser. Nothing you enter is stored or sent.
How this calculator works
- Drop length: the wall height plus a trimming allowance (10cm by default, 5cm at the top and bottom). For a patterned paper the drop is rounded up to a whole number of pattern repeats, so every drop starts at the same point in the pattern. A half-drop match adds half a repeat on average, as alternate drops start lower down.
- Drops per roll: the roll length ÷ the drop length, rounded down, since offcuts shorter than a drop are only good for above doors and windows.
- Drops needed: each wall's width ÷ the roll width, rounded up, then added together. A 4 × 3.5m room has two walls of 8 drops and two of 7: 30 drops.
- Rolls: drops needed ÷ drops per roll, rounded up. With 2.4m walls and a free-match paper, each 10.05m roll gives 4 drops of 2.5m, so 30 drops need 8 rolls.
Doors and windows aren't taken off. The short pieces above and below them come from roll offcuts, and the spare drops cover mistakes. For a room with large patio doors or a wide opening, use "Wall by wall" and leave that width out.
Standard roll sizes
| Roll | Width | Length | Area |
|---|---|---|---|
| UK and European standard | 0.53m | 10.05m | 5.3m² |
| Wide (some designer papers) | 0.68 to 0.70m | 10.05m | about 7m² |
| Extra wide (often paste-the-wall vinyl) | 1.06m | 10.05m | 10.6m² |
Tips
- Check the batch number. Every roll should have the same batch (or shade) number, because colours vary slightly between print runs. Buy them all at once.
- Buy a spare roll. It covers mistakes and future repairs, and many shops take unopened rolls back. A matching batch is hard to find later.
- Hang the first drop to a plumb line, not the corner of the room, since corners are rarely straight.
- Prepare the walls. Fill and sand, then size bare plaster (or use lining paper) so the paper slides into place and comes off later.
- Just one wall? A feature wall works well with the wall panelling calculator, and the paint calculator works out the paint for the other walls.
- Tiling a splashback or bathroom wall? The tile calculator works out the tiles, adhesive and grout.
Frequently asked questions
How many rolls of wallpaper do I need for a room?
For an average 4 × 3.5m room with 2.4m walls, about 8 standard rolls of a plain or free-match paper, or 10 for a paper with a 53cm straight-match repeat. Add one spare.
What is a pattern repeat?
The distance down the paper before the pattern starts again. It's on the label in centimetres. The bigger the repeat, the more paper is wasted lining up each drop.
What's the difference between straight and half-drop match?
With a straight match the pattern lines up straight across from drop to drop. With a half-drop match each drop is moved down by half a repeat, so you cut alternate drops from a different point and waste more.
How many drops are in a roll of wallpaper?
A standard 10.05m roll gives 4 drops for walls up to about 2.4m high with a plain paper. With a large repeat or higher ceilings it can drop to 3.
Should I take off windows and doors?
Usually not. The bits above and below them use offcuts, and you need spare for matching. Only leave out very wide openings.
Does it save or send what I type?
No. Everything is worked out in your browser, and nothing is stored or sent anywhere.
Results are estimates to help you plan. Rooms, papers and hanging methods vary, so check the roll label and follow the manufacturer's hanging instructions.