Wallpaper calculator
How many rolls of wallpaper you need for a room or one wall, counted strip by strip with the pattern repeat, the way the paper actually gets cut.
Your walls take
10 rolls
- Roll
- double roll, 20.5 in. × 33 ft
- In single rolls
- 20 single rolls
- Strips to cut
- 29 × 8 ft 4 in
- Strips per roll
- 3, 96 in left over
- Wall area
- 384 sq ft (48.0 ft of wall)
- Paper bought
- 564 sq ft (56.4 a roll)
- Square-foot check
- 16 single rolls
- Estimated cost
- A strip is longer than the roll. Use a longer roll or ask the seller about bolts sold by the yard.
Each strip is the wall height plus 4 in. for trimming, lengthened to whole pattern repeats. Doors and windows aren't subtracted, as Thibaut recommends: the leftover pieces paper above doors and under windows. The square-foot check divides the wall area by the Wallcoverings Association's 25 usable sq ft per single roll for this repeat. Strips include your extra (29 without it). Thibaut suggests ordering up to 20% more to allow for repeats, complicated rooms and mistakes.
How much wallpaper do I need?
Wallpaper goes up in vertical strips, and a roll only gives as many whole strips as fit along its length. So the calculator counts strips, the way Thibaut's wallpaper calculator does, instead of dividing square feet by the roll's area:
- Wall width = 2 × (length + width) for a room, or the width of the wall
- Strips = wall width ÷ roll width, rounded up
- Strip length = wall height + 4 in. (Graham & Brown: 2 in. at the top and bottom for trimming), rounded up to a whole number of pattern repeats
- Strips per roll = roll length ÷ strip length, rounded down
- Rolls = strips (plus any extra) ÷ strips per roll, rounded up
Worked example
A 12 × 12 ft room with 8 ft walls has 48 ft of wall. With double roll, 20.5 in. × 33 ft rolls, that's 576 in. ÷ 20.5 in. = 28.1, so 29 strips. With a 20.5 in. pattern repeat, each strip is 96 + 4 = 100 in., lengthened to 5 repeats = 102.5 in. (8 ft 6 1/2 in). A 33 ft roll is 396 in., which gives 3 whole strips and 88 1/2 in left over. 29 strips ÷ 3 per roll rounds up to 10 rolls.
Wallpaper roll sizes
Typical sizes from makers' and sellers' product pages. Rolls vary by brand and collection, so use the width, length and repeat on your roll's label or product page (pick "Another size" above).
| Roll | Covers | Example repeat | Source |
|---|---|---|---|
| Double roll, 20.5 in. × 33 ft | 56.4 sq ft | 20.5 in. | York Wallcoverings, Magnolia Home Colette (MF4747) |
| Double roll, 27 in. × 27 ft (9 yd) | 60.8 sq ft | 24 in. | Thibaut Baldwin Herringbone |
| Peel-and-stick roll, 20.5 in. × 18 ft | 30.8 sq ft | 20.9 in. | Brewster NuWallpaper Main Squeeze |
Usable square feet per single roll
The Wallcoverings Association, How to Estimate chart for the square-foot method: what a single roll really covers once the pattern is matched. A double roll is two single rolls. The association says the figures don't apply to walls under 3 ft or over 9 ft high.
| Pattern repeat | Single roll | Double roll |
|---|---|---|
| 0 to 6 in. | 25 sq ft | 50 sq ft |
| 7 to 12 in. | 22 sq ft | 44 sq ft |
| 13 to 18 in. | 20 sq ft | 40 sq ft |
| 19 to 23 in. | 18 sq ft | 36 sq ft |
Rolls for common rooms
Double roll, 20.5 in. × 33 ft rolls, 8 ft walls, no extra, counted by strips.
| Room | Wall area | Plain paper | 20.5 in. repeat |
|---|---|---|---|
| 10 × 10 ft | 320 sq ft | 8 rolls | 8 rolls |
| 12 × 12 ft | 384 sq ft | 10 rolls | 10 rolls |
| 12 × 14 ft | 416 sq ft | 11 rolls | 11 rolls |
| 14 × 16 ft | 480 sq ft | 12 rolls | 12 rolls |
Wallpaper questions
How much wallpaper do I need for a 12x12 room?
With 8 ft walls, a 12 × 12 room has 384 sq ft of wall. Counted by strips, it takes 10 double roll, 20.5 in. × 33 ft rolls of a plain paper and 10 with a 20.5 in. repeat. The Wallcoverings Association's own example, the same room with one door, two windows and an 8 in. repeat, comes to 339 sq ft ÷ 22 = 16 single rolls, or 8 double rolls. The strip count is higher because it assumes no strip is pieced together from leftovers; an experienced hanger can often use them over doors and windows and buy less.
How do you calculate wallpaper with a pattern repeat?
Make each strip a whole number of repeats long, so the pattern lines up from strip to strip. Take the wall height plus 4 in. for trimming and round it up to the next multiple of the repeat: for an 8 ft wall and a 20.5 in. repeat, 100 in. becomes 102.5 in. Then count how many of those strips fit on a roll. The repeat is printed on the label or product page. A drop or half-drop match shifts every other strip, which wastes more; add extra strips above for those.
How many square feet does a roll of wallpaper cover?
A double roll, 20.5 in. × 33 ft roll is 56.4 sq ft, and a peel-and-stick roll, 20.5 in. × 18 ft roll is 30.75 sq ft. Not all of it ends up on the wall: the Wallcoverings Association counts 25 usable sq ft per single roll for repeats up to 6 in., falling to 18 sq ft for repeats up to 23 in. That's why "wall square feet ÷ roll square feet" comes up short; the calculator shows the square-foot check next to the strip count.
Should I subtract doors and windows?
For the strip count, no. Thibaut says deducting them isn't recommended, because you still need paper above every door and above and below every window, and those short pieces come from the ends of rolls. In the square-foot method the Wallcoverings Association does subtract them, at about 21 sq ft for a standard door and 12 sq ft for a window. A wall that's mostly glass, or a wide opening with no wall above it, is different: leave that width out of the wall width.
How much peel and stick wallpaper do I need?
Peel-and-stick rolls are shorter, so each gives fewer strips. A 10 ft accent wall, 8 ft high, takes 6 strips of 104.5 in. with a 20.9 in. repeat; a 18 ft roll gives 2 of them, so you need 3 rolls. Press "Peel-and-stick wall" above to start from it. Peel-and-stick goes on smooth, painted walls, not textured ones; check the maker's instructions.
What's the difference between a single and a double roll?
A double roll is twice the length of a single roll on one spool. Many US sellers price wallpaper by the single roll but only sell it in double rolls, as Thibaut does, so a price "per roll" may be per single roll. The calculator counts the rolls you'll actually receive and shows the single-roll count for double rolls, so you can compare it to the price.