Walls & Wall Decor

Wallpaper Roll Calculator

Calculate wallpaper rolls from wall perimeter, height, roll size, pattern repeat, and full-height exclusions.

Wall-finish planning tool

Set the wall and product details for Wallpaper Roll Calculator

Method for this tool

What the Wallpaper Roll Calculator actually calculates

With a positive pattern repeat, drop length is rounded up to the next repeat multiple; a zero repeat leaves the entered height unchanged. Required drops come from wall run minus full-height excluded width, rounded up by roll width. Only complete drops fit within a roll, and a roll too short for one drop produces a calculation error rather than a roll estimate. There is no separate trimming allowance or half-drop matching model.

The calculation path

Usable drops per roll and required drops are calculated separately so pattern repeat is respected.

Inputs that can change the answer

Wall perimeter: Enter wall perimeter in m.
Wall height: Enter wall height in m.
Roll length: Enter roll length in m.
Roll width: Enter roll width in m.
Pattern repeat: Vertical repeat in metres. Zero is plain paper; positive repeats round the entered height upward to a complete repeat.
Full-height excluded width: Enter full-height excluded width in m.

Checks that stay outside the formula

Exclude only full-height gaps; ordinary doors and windows still need paper above or below. Order matching dye lots.

A practical order for entering the data

Measure the total wall run and height, then enter the wallpaper roll length and width in metres.
Enter the vertical pattern repeat, or zero for plain paper, and exclude only full-height gaps that need no paper.
Check that the calculated cut drop fits within one roll before relying on drops per roll or roll count.

Project walkthrough: Wall finishes: wallpaper, panels, and gallery layouts

Engine check using the prefilled sample

Worked example: wall perimeter = 15 m, wall height = 2.7 m, roll length = 10.05 m, roll width = 0.53 m, pattern repeat = 0.32 m and full-height excluded width = 1.8 m. Replace the sample wall and item dimensions with the exact section and product format involved in your layout.

Results for these inputs

Cut drop length: 2.88 m
Drops required: 25 drops
Drops per roll: 3 drops
Rolls required: 9 rolls

Project-specific method

Worked example and purchase checks

The tool estimates how many full-height drops can be cut from one roll after allowing for pattern repeat, then compares those drops with the usable wall width. It works from drops rather than dividing wall area by roll area.

Illustrative worked example

A patterned wallpaper project with a 640 mm repeat and one doorway treated as a full-height excluded width.

Exact inputs for this example

Wall perimeter	13.8 m
Wall height	2.55 m
Roll length	10.05 m
Roll width	0.53 m
Pattern repeat	0.64 m
Full-height excluded width	1.65 m

Cut drop length: 2.56 m
Drops required: 23 drops
Drops per roll: 3 drops
Rolls required: 8 rolls

How to read the result

The whole-roll result is a starting purchase quantity. Confirm the repeat type, usable roll length, and actual wall sequence before placing the order.

Assumptions this example makes

One wall height and one wallpaper roll specification apply to the calculation.
The entered excluded width represents full-height openings where no drop is needed.

What this calculator does not prove

Partial drops above doors/windows, pattern placement, damaged lengths, corner trimming, and batch matching are not optimized.
Manufacturer matching instructions take priority over a generic repeat calculation.

Wallpaper drop planningSketch is explanatory, not to scale.

Mistakes that change this result

Using roll area only and ignoring the number of full drops per roll.
Subtracting opening area instead of the full-height width requested by this tool.
Mixing centimetres from the product label with metre inputs.