How to use
Enter the room length and width, the wall height and the total width of doors and windows. Add the roll width and length from the label and the pattern repeat, if there is one. You’ll see how many strips you need, how many strips you get from one roll and how many rolls to buy.
For a drop match (the label shows offset arrows), choose “Drop match”: on average each strip needs half a repeat more. The area to cover helps estimate paste.
US wallpaper rolls
In the US, wallpaper is often priced per single roll but sold in double rolls. A typical double roll is about 20.5 in wide and 33 ft long — roughly 56 sq ft. Those are the defaults; check your label, since European rolls are usually 0.53 × 10.05 m (about 21 in × 33 ft) and some papers are 27 in wide.
How it’s calculated
- Perimeter to cover = 2 × (length + width) − width of doors and windows.
- Strips = perimeter ÷ roll width, rounded up.
- Strip length = wall height + about 4 in for trimming. With a pattern repeat, it’s rounded up to a whole number of repeats so the pattern lines up with the next strip.
- Strips per roll = roll length ÷ strip length, rounded down — a leftover piece shorter than the wall is no use for a full strip.
- Rolls = strips ÷ strips per roll, rounded up.
Examples
- A 16 × 13 ft room with 8 ft walls, a 3 ft door and a 3 ft window, double rolls of 20.5 in × 33 ft with no repeat: 31 strips, 3 per roll, 11 double rolls.
- The same paper with a 21 in repeat: each strip is 8.75 ft, you still get 3 per roll — 11 rolls.
- With 9 ft ceilings: strips of about 9.3 ft, still 3 per roll — 11 rolls.
FAQ
What is the pattern repeat? The vertical distance after which the pattern repeats. It’s printed on the label in inches. Plain papers and “random match” patterns have no repeat — enter 0.
Should I subtract whole windows? Only their width is subtracted. The short pieces above and below windows and over doors usually come from offcuts.
Should I buy an extra roll? Yes, for busy patterns or uneven walls — rolls from a different run (dye lot) can differ slightly in shade.
Painting instead? Try the paint calculator.