Wallpaper Calculator — Rolls, Pattern Repeat & Cost
Estimate wallpaper rolls for rooms or separate walls. Account for strip rounding, trim, straight or half-drop repeat, reserve, reusable offcuts, leftover length, and cost.
Measure a rectangular room
Each wall is rounded to a whole strip, so corners are not hidden by a perimeter-only estimate.
Doors, windows, and reusable offcuts
Wallpaper is normally ordered by full drops. Keep offcut credit disabled unless matched pieces around large openings can actually be reused.
Roll and pattern match
Use the dimensions and repeat printed on the roll label. Half-drop is estimated conservatively with an extra half-repeat alignment allowance.
Strip and seam preview
Roll breakdown
| Gross wall area | |
| Openings / net area | |
| Full strips before credit | |
| Reusable offcut credit | |
| Reserve strips | |
| Typical strips per roll | |
| Purchased coverage | |
| Roll length left over |
How the wallpaper estimate is calculated
Wallpaper calculator with pattern repeat
The usable drop is wall height plus trim, rounded up to the next repeat for straight match. Half-drop adds a conservative half-repeat alignment allowance before rounding.
How to measure for wallpaper
Measure each wall width and height. Room mode rounds all four walls separately; Wall sections mode supports feature walls and mixed heights. Do not rely only on square footage because rolls must yield full vertical strips.
Doors, windows, and wallpaper offcuts
Installers usually cut full drops and trim around openings, so doors and windows do not reduce the default roll count. Enable reusable offcut credit only when the repeat and offcut sizes allow matched pieces to be reused.
Wallpaper rolls, cost, and installation
The planner packs drops of different lengths into whole rolls, shows leftover roll length and purchased coverage, and multiplies rolls by price. Paste, primer, tools, labor, shipping, and tax are not included.
