Wallpaper Calculator

For a 12x12 room with 8-foot ceilings, 1 door, and 2 windows: approximately 7 double rolls with no pattern repeat. Add 1-2 more double rolls if the wallpaper has a large pattern repeat (over 21 inches). This calculator adjusts automatically based on your specific pattern repeat and match type.

Pattern repeat is the vertical distance between one point in the pattern and where that exact point appears again. A 24-inch repeat means the pattern cycle is 24 inches tall. Larger repeats mean more waste per strip because you must align each strip perfectly. Check the wallpaper label or product listing for the repeat measurement.

Straight match aligns the pattern horizontally at the same position on every strip. Half-drop shifts every other strip down by half the repeat distance, creating a diagonal flow. Half-drop produces more waste (20-25% vs 10-15% for straight match) because the effective repeat cycle doubles.

At minimum 10-15% extra for trimming and cutting waste. For wallpaper with a pattern repeat, add 15-25% extra depending on the repeat size. This calculator includes a 1-roll safety margin automatically. Always order all rolls from the same dye lot to avoid color variation between batches.

Wallpaper is priced per single roll but sold in double rolls (bolts). A US single roll covers about 28 sq ft while a double roll covers about 56 sq ft. You cannot buy individual single rolls from most manufacturers. This calculator shows results in double rolls since that is what you actually purchase.

Yes. Peel-and-stick comes in panels (typically 24 inches wide) rather than standard rolls. This calculator handles peel-and-stick as a separate roll type with the correct panel dimensions. Pattern waste is generally lower since panels can be repositioned during installation.

Measure the wall width and height in feet. Switch this calculator to "Accent Wall" mode and enter those dimensions. The calculator subtracts any doors or windows you specify. Most accent walls need just 2-3 double rolls, making them the most cost-effective way to add wallpaper to a room.

Yes. Order all rolls from the same dye lot (batch number printed on each roll). Even the same wallpaper pattern from the same manufacturer can have subtle color shifts between production runs. If you need to reorder later, the new batch may not match your existing walls.