Wallpaper Calculator

A 12×12 ft wall equals 144 gross square feet. With standard US double rolls (56.4 sq ft nominal area, approx 50 sq ft usable coverage after trimming), you will need 3 standard double rolls (or 6 single rolls) for plain/random match paper. If your wallpaper has a straight or half-drop pattern repeat (>18 inches), order 4 double rolls to account for vertical pattern alignment offcuts and reserve dye-lot matching spares.

A standard 10m European metric roll (10.05m length × 53cm width) has a nominal area of 5.33 m² (approx 56.8 sq ft). In practice, allowing for standard 8 to 9 ft ceiling cuts and top/bottom trimming margins, one 10m roll yields 3 full strips and covers approximately 4.5 to 4.8 m² (approx 48 to 52 square feet) of usable wall surface for solid or random patterns.

A standard 10×10 ft room has a 40-foot perimeter. With standard 8-foot ceilings, the gross wall area is 320 sq ft. After deducting standard openings (1 door ≈ 21 sq ft, 1 window ≈ 15 sq ft) to reach 284 net sq ft, you will need 6 to 7 standard US double rolls (or 7 to 8 Euro rolls), including a 10% safety buffer for cuts and dye-lot spares.

For 300 square feet of net wall area, you will need 6 to 7 standard US double rolls (each providing ~50 sq ft usable area) or 12 to 14 US single rolls. If you are ordering 36-inch wide natural grasscloth sold by the linear yard, you will need approximately 34 to 36 linear yards.

Wallpaper for a 12×12 ft wall (144 sq ft, requiring 3 double rolls) typically costs between $90 and $450+ for materials: Budget peel-and-stick ($30–$50/roll = $90–$150), Mid-range designer non-woven ($60–$100/roll = $180–$300), and Luxury grasscloth/textured vinyl ($150–$250+/roll = $450–$750+). Professional installation labor typically adds $200–$400.

To calculate wallpaper accurately: (1) Measure total wall width and ceiling height in feet to get gross area (Width × Height). (2) Subtract 21 sq ft per standard door and 15 sq ft per window. (3) Divide net square footage by your roll's usable area (50 sq ft for plain US double rolls; 42–46 sq ft for patterned). (4) Add a 10% safety buffer and round up to the nearest whole roll. Use our free YesMeasure calculator above for exact strip-by-strip cut breakdowns.

In North America, wallpaper prices are often quoted per 'Single Roll,' but wallpaper is almost universally manufactured, packaged, and shipped in continuous 'Double Rolls' (20.5 in wide × 33 ft long = 56.4 sq ft). A double roll provides twice the continuous length of a single roll (16.5 ft), allowing 3 full 8-to-9 ft ceiling drops per roll with minimal offcut scrap.

A straight match means pattern motifs align horizontally across adjacent strips at exactly the same vertical height (10–15% waste allowance). A half-drop match shifts the pattern downward by half of a repeat on alternating strips to create diagonal flow (15–25% waste allowance). Half-drop patterns require more roll yardage because every second strip must be trimmed down to align the motif.

For small windows or single interior doors, professional paperhangers recommend not subtracting them, because full vertical drops of wallpaper are still cut and hung above and below the openings. For large architectural openings such as sliding glass patio doors, double French doors, or wide picture windows (>30 sq ft), subtract their square footage to avoid over-purchasing.

Wallpaper is printed in discrete production runs called dye lots or run numbers. Rolls from different runs frequently exhibit slight shade, sheen, or ink density variations that appear glaringly mismatched when hung side-by-side on a wall. Always check that all rolls share identical batch/run numbers before opening packaging.