The practical toolbox

Wallpaper roll calculator

Calculate how many wallpaper rolls you need from wall and roll sizes. Allow for trimming, straight-match pattern repeats and spare rolls, then save your estimate.

MeasurementsChoose your units. Costs, watts and time stay the same.

Save this version with its URL. Bookmark this page or copy its link to reopen your inputs later. Save a new link after making changes. Anyone with the link can read your inputs. Results are recalculated on reopening; print a copy if you need a fixed record.

Create a saved link with AI

Give your AI assistant your measurements or figures and the instructions below. It can create a ready-to-open link for this wallpaper roll calculator. Open the link, check the inputs, then bookmark it or copy the URL to reuse it later.

Copy this prompt and add your information:

Read https://www.lejnel.com/wallpaper-rolls-url-guide.txt and generate a clickable saved-plan URL for my wallpaper roll calculator. Convert my units to the guide’s required units. Ask for missing inputs instead of guessing, and explain any assumptions. Return the link and a summary of the inputs used.

Read the URL format and examples · AI instructions for all tools

The URL contains your inputs. Anyone with the link can read them. Future calculator updates may change results; retain a printed copy when you need a fixed record.

Wall and roll measurements

For walls of equal height, add their widths. Use the highest measured height. Enter the roll’s actual labelled dimensions.

Trimming is the combined top and bottom allowance. Use the amount your installer or instructions require. For a repeating straight match, every cut is rounded up to a complete repeat. Half-drop, offset and reverse-hang layouts are outside this calculator.

Your roll estimate

How many wallpaper rolls do I need?

Divide wall width by roll width and round up to find the number of full-height strips. Divide the roll length by the cut length and round down to find strips per roll. Divide strips needed by strips per roll and round up to whole rolls.

How to measure for wallpaper

  1. Measure the wall width and the height at several points. Use the greatest height. Combine widths only where the paper and planning height are the same.
  2. Read the width and continuous length from the roll label. Enter the length of one physical roll, rather than a single-roll pricing unit if the pack contains a longer roll.
  3. Enter the usable roll length after any damaged ends or initial pattern-alignment cut required by your paper.
  4. Add the combined top and bottom trimming allowance specified for your job. Enter 0 for free match, or the vertical repeat for a straight match. Check the label: offset and half-drop matches need a different cutting plan.
  5. Choose any extra whole rolls yourself, then review the strip count and roll estimate with your supplier before ordering.

Pattern repeat and trimming

Cut length starts with wall height plus your total top-and-bottom trimming allowance. For a straight match, it is rounded up to a multiple of the vertical repeat. This assumes every roll starts at the same usable motif phase. If the label requires an initial pattern-alignment cut or has unusable ends, subtract those from the usable roll length yourself before entering it.

For definitions of vertical repeat and match types, see Graham & Brown’s wallpaper FAQ. Always use the instructions for your own paper.

Worked example

A 6,000 mm wall needs 12 strips of 530 mm paper. A 2,400 mm height plus 100 mm total trimming gives 2,500 mm cuts. A 10,000 mm usable roll gives four strips, so three rolls cover the wall. With a 640 mm straight repeat, the cut becomes 2,560 mm, giving three strips per roll and four rolls total. All values are examples.

Free match

6,000 mm width, 2,400 mm height, 100 mm trimming and a 530 × 10,000 mm usable roll: 12 strips, 4 per roll, 3 rolls.

640 mm straight repeat

The same dimensions with repeat rounding: 2,560 mm cuts, 3 strips per roll, 4 rolls.

One spare roll

Add one extra roll to the straight-match example: 5 rolls to buy. Spares are your choice, not an automatic requirement.

Should I subtract doors and windows?

No deductions are made here. Keeping full-height strips across openings is a conservative starting point; a real cutting plan may reuse offcuts above or below openings. This calculator does not optimize those cuts or join short pieces into a strip.

Can I combine walls?

Add widths only for walls using the same paper and planning height. Corner overlap, separate wall starts and uneven walls can require more strips. Include any required additional covered width in your measurement, or calculate walls separately for a more conservative order.

Can I use imperial measurements?

Yes. The shared unit control changes displayed dimensions to inches while saved inputs remain millimetres. Bookmark the complete copied URL to retain an estimate.

Why can pattern repeat increase the roll count?

A repeat can make each full-height cut longer, so fewer complete strips fit on each roll. Small unused tails from different rolls cannot be joined into a full-height strip in this estimate. Area alone can miss this rounding effect.

Does this support half-drop wallpaper?

No. Half-drop and offset matches require staggered pattern positions between adjacent strips. This calculator supports free match and straight match only; use your supplier’s product-specific calculator or a cutting plan for other matches.

Can I save and print my estimate?

Copy the estimate link and bookmark the complete URL to reopen the inputs. After editing, copy a new link. Print the results to keep a fixed record of the measurements and quantities.

Assumptions and responsibility

This tool counts identical full-height cuts from identical usable rolls; it does not prescribe a trimming allowance, matching method or spare quantity. It excludes half-drop/offset matching, borders, murals, defects, slopes, batch matching and installation design. Confirm the order with your supplier, including matching batch numbers and returns. Figures are estimates without warranty; you remain responsible for measurements, suitability and purchases. Nothing limits rights that cannot legally be excluded. See our terms. Printed diagrams are schematic, not cutting templates.

Also try the paint calculator or curtain width calculator.