Wallpaper Calculator
Calculate how many rolls of wallpaper you need, including pattern repeat and waste factor.
Common Wallpaper Roll Sizes
| Region / Type | Width | Length | Sq Ft / Roll |
|---|---|---|---|
| US Single Roll | 20.5 in | 27 ft | ~46 |
| US Double Roll | 20.5 in | 54 ft | ~92 |
| European (metric) | 20.9 in | 33 ft | ~57 |
| Wide format | 27 in | 27 ft | ~60 |
Frequently Asked Questions
What is a standard wallpaper roll size?
US single rolls of wallpaper are typically 27 feet long and 20.5 inches wide, yielding about 56 square feet. However, wallpaper is often sold in double rolls (54 ft long) for convenience. European rolls are commonly 33 ft long and 20.9 in wide. Always check the specific roll dimensions on the product label before ordering.
How does pattern repeat affect how many rolls I need?
A patterned wallpaper must be aligned at each seam — this wastes material. The pattern repeat is the vertical distance before the pattern repeats. A 24-inch repeat means you lose up to 24 inches from each drop (vertical strip). For a ceiling height of 8 ft, this can require strips 9–10 ft long instead of 8 ft. Small or zero-repeat patterns waste the least.
Should I deduct area for doors and windows?
Yes — this calculator deducts standard door area (~21 sq ft each) and window area (~15 sq ft each). However, because wallpaper must be cut to size, pieces above and below doors and windows often cannot be reused for full drops. Some professionals calculate doors and windows as half deductions to account for this.
How much extra wallpaper should I order?
Order at least 10% extra for waste — this calculator applies 10% automatically. For patterned wallpaper with large repeats, add 15–20%. Always try to order all rolls from the same production batch (same batch number) to ensure color consistency. Dye lots can vary between batches.
Can I wallpaper over existing wallpaper?
It is generally not recommended. Old wallpaper seams can telegraph through new wallpaper, and old adhesive may not hold well under the additional weight. Moisture from new wallpaper paste can loosen old wallpaper and cause bubbles. Remove old wallpaper first for the best results, and prime the walls before hanging new paper.