Calculate Wallpaper

Wallpaper Roll Calculator

Use this calculator to estimate how many rolls of wallpaper you'll need for your project. Accurate measurements are key!

function calculateWallpaper() { // Get input values var totalWallLength = parseFloat(document.getElementById("totalWallLength").value); var wallHeight = parseFloat(document.getElementById("wallHeight").value); var rollWidth = parseFloat(document.getElementById("rollWidth").value); var rollLength = parseFloat(document.getElementById("rollLength").value); var patternRepeat = parseFloat(document.getElementById("patternRepeat").value); var wastePercentage = parseFloat(document.getElementById("wastePercentage").value); // Validate inputs if (isNaN(totalWallLength) || totalWallLength <= 0 || isNaN(wallHeight) || wallHeight <= 0 || isNaN(rollWidth) || rollWidth <= 0 || isNaN(rollLength) || rollLength <= 0 || isNaN(patternRepeat) || patternRepeat < 0 || isNaN(wastePercentage) || wastePercentage 0) { // The length of each drop must be a multiple of the pattern repeat that is greater than or equal to the wall height. effectiveDropLength = Math.ceil(wallHeight / patternRepeat) * patternRepeat; } // Step 2: Calculate how many drops can be cut from a single roll var dropsPerRoll = Math.floor(rollLength / effectiveDropLength); if (dropsPerRoll <= 0) { document.getElementById("wallpaperResult").innerHTML = "Error: Your wall height or pattern repeat is too large for the roll length. Please check your measurements."; return; } // Step 3: Calculate the total number of drops needed for all walls var totalDropsNeeded = Math.ceil(totalWallLength / rollWidth); // Step 4: Calculate the number of rolls needed before accounting for waste var rollsBeforeWaste = totalDropsNeeded / dropsPerRoll; var roundedRollsBeforeWaste = Math.ceil(rollsBeforeWaste); // Step 5: Apply the waste percentage var finalRolls = roundedRollsBeforeWaste * (1 + wastePercentage / 100); var totalRollsRequired = Math.ceil(finalRolls); // Step 6: Calculate total area covered by the required rolls (for informational purposes) var totalWallpaperArea = totalRollsRequired * rollWidth * rollLength / 10000; // Convert cm^2 to m^2 // Display results var resultHtml = "

Calculation Results:

"; resultHtml += "Effective Drop Length: " + effectiveDropLength.toFixed(0) + " cm (length of each cut strip)"; resultHtml += "Drops Per Roll: " + dropsPerRoll.toFixed(0) + " (number of strips you can get from one roll)"; resultHtml += "Total Drops Needed: " + totalDropsNeeded.toFixed(0) + " (total strips required for your walls)"; resultHtml += "Estimated Rolls (before waste): " + roundedRollsBeforeWaste.toFixed(0) + ""; resultHtml += "Total Wallpaper Rolls Required: " + totalRollsRequired.toFixed(0) + " rolls"; resultHtml += "Estimated Total Wallpaper Area: " + totalWallpaperArea.toFixed(2) + " m²"; document.getElementById("wallpaperResult").innerHTML = resultHtml; } .wallpaper-calculator-container { font-family: Arial, sans-serif; max-width: 700px; margin: 20px auto; padding: 25px; border: 1px solid #ddd; border-radius: 8px; background-color: #f9f9f9; box-shadow: 0 2px 5px rgba(0,0,0,0.1); } .wallpaper-calculator-container h2 { color: #333; text-align: center; margin-bottom: 20px; } .wallpaper-calculator-container p { color: #555; line-height: 1.6; } .calculator-form .form-group { margin-bottom: 15px; } .calculator-form label { display: block; margin-bottom: 5px; font-weight: bold; color: #444; } .calculator-form input[type="number"] { width: calc(100% – 22px); padding: 10px; border: 1px solid #ccc; border-radius: 4px; box-sizing: border-box; font-size: 16px; } .calculator-form small { display: block; color: #777; margin-top: 5px; font-size: 0.9em; } .calculator-form button { display: block; width: 100%; padding: 12px 20px; background-color: #007bff; color: white; border: none; border-radius: 4px; font-size: 18px; cursor: pointer; margin-top: 20px; transition: background-color 0.3s ease; } .calculator-form button:hover { background-color: #0056b3; } .calculator-result { margin-top: 25px; padding: 15px; border: 1px solid #e0e0e0; border-radius: 4px; background-color: #eaf4ff; color: #333; } .calculator-result h3 { color: #007bff; margin-top: 0; margin-bottom: 10px; } .calculator-result p { margin-bottom: 8px; } .calculator-result .highlight { font-size: 1.2em; font-weight: bold; color: #28a745; /* Green for emphasis */ } .calculator-result .error { color: #dc3545; font-weight: bold; }

Understanding Wallpaper Calculation

Wallpapering a room can dramatically transform its look and feel, but getting the right amount of wallpaper is crucial. Ordering too little means delays and potential color batch differences, while ordering too much leads to unnecessary waste and cost. Our Wallpaper Roll Calculator helps you accurately estimate the number of rolls you'll need for your project, taking into account key factors like wall dimensions, roll size, and pattern repeat.

Key Factors in Wallpaper Calculation:

1. Total Wall Length: This is the combined length of all walls you intend to wallpaper. For a rectangular room, you'd measure each wall and add them together. Remember to measure accurately, ideally at the top, middle, and bottom, and use the largest measurement.
2. Wall Height: Measure the height from the floor to the ceiling. Again, take measurements at several points and use the greatest height to ensure you have enough material for each drop.
3. Wallpaper Roll Width & Length: These are standard dimensions provided by the wallpaper manufacturer. Common widths are 53cm or 70cm, and lengths are often 1000cm (10 meters). Always check the label on your chosen wallpaper.
4. Pattern Repeat: If your wallpaper has a design that needs to align from one strip to the next, it will have a pattern repeat. This measurement (e.g., 32cm, 64cm) indicates how often the pattern repeats vertically. This is a critical factor as it means you'll need to cut each strip slightly longer to allow for matching, leading to more waste. Plain wallpapers or those with random matches have a pattern repeat of 0.
5. Waste & Trim Percentage: It's always wise to factor in extra material for trimming, mistakes, and future repairs. For plain or random match wallpapers, 5-10% is usually sufficient. For patterned wallpapers, especially those with large repeats, 10-15% is a safer bet. Our calculator includes this percentage to give you a more realistic estimate.

How the Calculator Works:

The calculator uses a step-by-step process to determine your wallpaper needs:

1. It first calculates the effective length of each wallpaper drop. If there's a pattern repeat, it ensures each drop is cut to a length that is a multiple of the pattern repeat, guaranteeing the pattern aligns correctly.
2. Next, it determines how many of these effective drops can be cut from a single roll of your chosen wallpaper.
3. Then, it calculates the total number of drops required to cover the entire length of your walls, based on the roll's width.
4. Finally, it divides the total drops needed by the drops per roll to get an initial estimate of rolls, rounds up, and then applies your specified waste percentage to give you the final, recommended number of rolls.

Example Calculation:

Let's say you have a room with a total wall length of 1200 cm (12 meters) and a wall height of 250 cm (2.5 meters). You've chosen a wallpaper with a roll width of 53 cm, a roll length of 1000 cm (10 meters), and a pattern repeat of 64 cm. You want to add a 10% waste margin.

• Effective Drop Length: Since the wall height (250 cm) is not a multiple of the pattern repeat (64 cm), we find the next multiple: Math.ceil(250 / 64) * 64 = 4 * 64 = 256 cm. Each strip will be cut to 256 cm.
• Drops Per Roll: From a 1000 cm roll, you can get Math.floor(1000 / 256) = 3 drops.
• Total Drops Needed: For a total wall length of 1200 cm and a roll width of 53 cm, you'll need Math.ceil(1200 / 53) = 23 drops.
• Rolls Before Waste: You need 23 drops, and each roll gives 3 drops, so Math.ceil(23 / 3) = 8 rolls.
• Final Rolls (with 10% waste): Math.ceil(8 * 1.10) = 9 rolls.

Based on these inputs, you would need to purchase 9 rolls of wallpaper.

Tips for Measuring and Ordering:

• Measure Twice: Always double-check your measurements to avoid errors.
• Account for Openings: For very large windows or doors, you might subtract their area from the total wall area, but for simplicity and to ensure enough material, many professionals calculate the full wall area and rely on the waste percentage to cover these minor deductions. Our calculator uses the full wall length for simplicity and safety.
• Batch Numbers: When ordering, ensure all your rolls come from the same batch number to avoid slight color variations.
• Consider Professional Help: If you're unsure about measuring or hanging, consider consulting a professional decorator.