Quantity & Materials Tool

Wallpaper Calculator

Estimate wallpaper rolls needed with pattern match.

Room & Roll Details

Enter 0 for no pattern / plain.

# About This Calculator

Wallpaper can dramatically change the vibe of a room, but calculating quantity is notoriously difficult due to pattern repeats. If you just measure square footage, you will almost certainly run short.

This calculator is "pattern-aware." It determines how many "drops" (vertical strips) you need and checks if the pattern repeat will force you to cut waste from each roll to make the design line up perfectly.

The "Double Roll" Confusion

In the US, wallpaper is priced by the "Single Roll" but almost always sold in "Double Rolls" (also called bolts).
Rule of Thumb: When this calculator tells you "Rolls," check if it matches the packaging. A standard American double roll is about 56-60 square feet.

What is a Pattern Repeat?

If your wallpaper has a large floral or geometric design, the image repeats every few inches (e.g., 18" or 24"). To make the flowers match horizontally across seams, you have to shift the paper up or down, wasting the excess. This tool accounts for that waste so you don't end up with mismatched seams.

How To Use

  1. Measure the **Width** and **Height** of the wall(s).
  2. Check the wallpaper label for **Roll Width**, **Roll Length**, and **Pattern Repeat**.
  3. Enter these values (use 0 for random/no match patterns).
  4. The result will tell you the **Total Rolls** to order.

Frequently Asked Questions

How do I calculate how much wallpaper I need?+

Measure your wall width and height to get the total square footage. Then, account for the roll coverage (standard rolls are ~25-30 sq ft usable) and pattern repeats, which add waste.

How many rolls of wallpaper for a 12x12 room?+

For a standard 12x12 room with 8ft ceilings, you would likely need 10-12 double rolls, depending on the pattern repeat and number of doors/windows.

Do I need to buy extra wallpaper for pattern matching?+

Yes. For large pattern repeats (e.g., 18 inches or more), we recommend buying 20-30% extra to ensure the design lines up correctly across the wall.

What is a double roll vs single roll?+

Most wallpaper is priced by the single roll but sold in double rolls. A double roll essentially contains two single rolls in one continuous strip. Always check the 'Total Sq Ft' on the label.

Should I deduct for windows?+

Generally, no. You still need full drops (strips) to go above and below the window, and trying to patch small pieces often ruins the pattern flow. Treat walls as solid for ordering.

Is Wallpaper Calculator free to use?+

Yes, Wallpaper Calculator on Matheric is completely free to use. We believe in accessible education and utility for everyone.

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