Room & Wallpaper Details

Roll Size Standard

US double roll selected: approx. 57 sq ft (5.3 m²) per roll — the most common format sold in American stores.

Units

Room Length

Room Width

Wall Height

Number of Doors

Number of Windows

Doors and windows are only deducted when they are large (patio doors, bay windows). For standard sizes, you'll still need full strips above and below each opening — so the calculator applies a partial credit only, as professional decorators recommend.

Pattern Match Type

No Pattern / Random Match

Solid colors or textures with no vertical repeat. Minimal waste — each strip can start at any point on the roll.

Straight Match

The pattern repeats horizontally at the same height on every strip. Each new strip must begin at the same point in the pattern — some of the roll is lost at each cut.

Half-Drop Match

The pattern shifts down by half a repeat on alternating strips. More complex alignment means more waste per strip — budget for at least one extra roll.

Your Estimate

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Fill in your room details and click Calculate Rolls to see how many rolls you need.

How to Use This Calculator

Measure the length and width of your room at floor level, and the height from floor to ceiling (or picture rail). Enter the number of standard doors and windows — the calculator applies a professional partial credit for openings rather than removing them entirely, because you still need full wallpaper strips above and below each door and window.

What Is Pattern Repeat?

Pattern repeat is the vertical distance after which a design starts again on the wallpaper roll. You'll find this number on the roll label or the product page, usually marked with a symbol that looks like two overlapping squares. A repeat of 0 means no alignment is needed. Larger repeats (25 cm / 10 in or more) increase waste significantly because each strip must be cut to start at the same point in the pattern.

Straight Match vs. Half-Drop

With a straight match, every strip starts at the same height in the pattern — the motif lines up horizontally across the wall. With a half-drop, alternating strips shift down by exactly half a repeat, creating a diagonal feel. Half-drop patterns are common in large florals and geometrics, and they waste more material because the offset cuts leave larger off-cuts at the top or bottom of each strip.

US vs. UK Roll Sizes

In the United States, wallpaper is typically sold in double rolls (also called a bolt), which cover approximately 57 square feet (5.3 m²). Single rolls are rarely sold individually. In the United Kingdom, the standard roll measures 10.05 m long by 530 mm wide, covering about 5.3 m² — which happens to be almost identical in area, but the strip length and width differ, affecting how many drops you get per roll.

Why You Should Never Run Out Mid-Job

Running short of wallpaper mid-room is one of the most common and costly decorating mistakes. Reordering even a single roll risks getting a different print batch — and the color difference, though subtle, becomes visible once the paper is on the wall. The calculator rounds up and includes a safety margin for this reason. Order everything at once, keep at least one spare roll, and store it flat.

Wallpaper Calculator