Estimate whole wallpaper rolls
Enter your actual wall and roll measurements. Choose metric or UK imperial units explicitly; no standard roll size is assumed.
Educational purchasing estimate, not an exact quantity or installation plan. Check the product label or specification, batch, pattern direction, adhesive and manufacturer instructions. Wall conditions, pattern matching and installation vary. Openings and offcuts are not optimised. Consult a qualified professional when preparation or safety requires technical assessment.
Clear this calculation and switch?
Changing locale or units clears every field and the current result. Values are not converted.
How the calculation works
Wall height plus the total trim allowance gives the starting drop length. For a straight-match pattern, the calculator rounds that length up to a whole pattern repeat; with a repeat of zero, it keeps the starting length. It rounds wall width divided by usable roll width up to whole drops, applies your additional-drop percentage and rounds up again. It then counts the complete drops that fit on one roll and rounds the required roll count up to whole rolls.
Fictitious example
Fictitious example: 4 m of wall width, a 2.6 m wall height, a 0.53 m × 10 m roll, a 0.64 m straight pattern repeat and 0.10 m total trim allowance, with 0% additional drops, need 8 drops. Each drop is adjusted to 3.2 m; 3 fit on each roll, so the estimate is 3 whole rolls. Replace every value with your measurements and the roll label.
Limitations
This calculator estimates whole rolls for walls of one height and straight-match patterns. It does not subtract doors or windows, combine different wall heights, handle offset or half-drop matching, or optimise offcuts. Check the roll label and the manufacturer's installation instructions before using the estimate.
Methodology
Formula version: wallpaper-en-v1. The formula's recorded review date is 24 August 2026. The calculation converts the selected measurements to millimetres internally; changing the form's unit system clears the entries instead of converting them. Use the actual wall measurements, usable roll width, roll length and pattern repeat, not a presumed standard roll size.
Wallpaper questions
How does pattern repeat affect drops per roll?
The calculator adds the total trim allowance to the wall height, then rounds that length up to a whole straight pattern repeat. It counts only complete drops that fit within the entered roll length, so a longer adjusted drop can reduce the number available from each roll. A repeat of 0 skips this adjustment; offset and half-drop matching are outside the calculation.
Does the calculator assume a standard UK roll size?
No: use the usable width and length stated for the actual roll, even when it differs from the example. Choose metric or UK imperial units explicitly; switching systems clears your entries and does not convert them. The 0.53 m × 10 m example is fictitious, not a required or assumed UK roll size.