.wallpaper-calculator-container {
font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
background-color: #f9f9f9;
padding: 25px;
border-radius: 10px;
box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
max-width: 700px;
margin: 30px auto;
border: 1px solid #e0e0e0;
}
.wallpaper-calculator-container h2 {
color: #333;
text-align: center;
margin-bottom: 25px;
font-size: 28px;
font-weight: 600;
}
.wallpaper-calculator-container .input-group {
margin-bottom: 18px;
display: flex;
flex-direction: column;
}
.wallpaper-calculator-container label {
margin-bottom: 8px;
color: #555;
font-size: 16px;
font-weight: 500;
}
.wallpaper-calculator-container input[type="number"] {
width: calc(100% – 20px);
padding: 12px;
border: 1px solid #ccc;
border-radius: 6px;
font-size: 16px;
box-sizing: border-box;
transition: border-color 0.3s ease;
}
.wallpaper-calculator-container input[type="number"]:focus {
border-color: #007bff;
outline: none;
box-shadow: 0 0 0 2px rgba(0, 123, 255, 0.25);
}
.wallpaper-calculator-container button {
background-color: #007bff;
color: white;
padding: 14px 25px;
border: none;
border-radius: 6px;
cursor: pointer;
font-size: 18px;
font-weight: 600;
margin-top: 20px;
width: 100%;
transition: background-color 0.3s ease, transform 0.2s ease;
}
.wallpaper-calculator-container button:hover {
background-color: #0056b3;
transform: translateY(-2px);
}
.wallpaper-calculator-container .result-section {
margin-top: 30px;
padding: 20px;
background-color: #e9f7ff;
border: 1px solid #cce5ff;
border-radius: 8px;
font-size: 17px;
color: #333;
line-height: 1.6;
}
.wallpaper-calculator-container .result-section p {
margin-bottom: 10px;
display: flex;
justify-content: space-between;
align-items: center;
}
.wallpaper-calculator-container .result-section p strong {
color: #0056b3;
font-size: 18px;
}
.wallpaper-calculator-container .result-section p:last-child {
margin-bottom: 0;
font-weight: bold;
color: #007bff;
font-size: 20px;
}
.wallpaper-calculator-container .error-message {
color: #dc3545;
margin-top: 15px;
text-align: center;
font-weight: 500;
}
.wallpaper-calculator-container .units-info {
font-size: 14px;
color: #777;
margin-top: -10px;
margin-bottom: 15px;
text-align: right;
}
.wallpaper-calculator-container .article-content {
margin-top: 40px;
padding-top: 30px;
border-top: 1px solid #eee;
color: #444;
line-height: 1.7;
}
.wallpaper-calculator-container .article-content h3 {
color: #333;
font-size: 24px;
margin-bottom: 15px;
font-weight: 600;
}
.wallpaper-calculator-container .article-content p {
margin-bottom: 15px;
}
.wallpaper-calculator-container .article-content ul {
margin-bottom: 15px;
padding-left: 20px;
}
.wallpaper-calculator-container .article-content ul li {
margin-bottom: 8px;
}
function calculateWallpaper() {
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);
var doorsWindowsArea = parseFloat(document.getElementById('doorsWindowsArea').value);
var errorMessageDiv = document.getElementById('errorMessage');
var wallpaperResultDiv = document.getElementById('wallpaperResult');
// Input validation
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 ||
isNaN(doorsWindowsArea) || doorsWindowsArea 0 && patternRepeat > wallHeight) {
errorMessageDiv.textContent = 'Pattern repeat cannot be greater than wall height unless it\'s 0.';
errorMessageDiv.style.display = 'block';
wallpaperResultDiv.style.display = 'none';
return;
}
// Calculations
var totalWallArea = totalWallLength * wallHeight;
var effectiveWallArea = totalWallArea – doorsWindowsArea;
if (effectiveWallArea 0) {
// Calculate how many pattern repeats fit into the wall height, then round up to ensure full repeats
var numRepeatsNeeded = Math.ceil(wallHeight / patternRepeat);
adjustedDropLength = numRepeatsNeeded * patternRepeat;
} else {
adjustedDropLength = wallHeight;
}
var dropsPerRoll = Math.floor(rollLength / adjustedDropLength);
if (dropsPerRoll <= 0) {
errorMessageDiv.textContent = 'Error: Wallpaper roll is too short to yield even one full drop with pattern repeat. Please check your measurements.';
errorMessageDiv.style.display = 'block';
wallpaperResultDiv.style.display = 'none';
return;
}
// Calculate total number of drops needed for the room's perimeter
var totalDropsNeeded = Math.ceil(totalWallLength / rollWidth);
// Calculate raw rolls needed based on drops
var rawRollsNeeded = totalDropsNeeded / dropsPerRoll;
// Apply waste percentage
var rollsWithWaste = rawRollsNeeded * (1 + wastePercentage / 100);
// Final rolls needed, always rounded up
var finalRollsNeeded = Math.ceil(rollsWithWaste);
// Display results
document.getElementById('displayTotalWallArea').textContent = totalWallArea.toFixed(2) + ' (or ' + effectiveWallArea.toFixed(2) + ' effective) units²';
document.getElementById('displayAdjustedDropLength').textContent = adjustedDropLength.toFixed(2) + ' units';
document.getElementById('displayDropsPerRoll').textContent = dropsPerRoll;
document.getElementById('displayTotalDropsNeeded').textContent = totalDropsNeeded;
document.getElementById('displayFinalRollsNeeded').textContent = finalRollsNeeded + ' rolls';
errorMessageDiv.style.display = 'none';
wallpaperResultDiv.style.display = 'block';
}
Wallpaper Roll Calculator
All measurements should be in the same unit (e.g., centimeters or inches).
Total Wall Area:
Adjusted Drop Length:
Drops per Roll:
Total Drops Needed:
Recommended Rolls to Buy:
Understanding Wallpaper Calculation
Calculating the correct amount of wallpaper for your project is crucial for a smooth and cost-effective renovation. Buying too little means delays and potential color/batch mismatches, while buying too much leads to unnecessary waste and expense. This calculator helps you determine the precise number of rolls you'll need, taking into account various factors.
Key Factors in Wallpaper Calculation
- Room Dimensions: The total length of all walls (perimeter) and the height of the walls are fundamental.
- Wallpaper Roll Dimensions: Rolls come in standard widths and lengths, which directly impact how many strips you can get from each roll.
- Pattern Repeat: If your wallpaper has a pattern, you'll need extra length on each strip to ensure the pattern aligns seamlessly across the wall. This is a common source of underestimation.
- Waste/Extra: It's always wise to factor in an additional percentage for trimming, mistakes, or future repairs. A 10-15% buffer is generally recommended.
- Doors and Windows: While you don't wallpaper over these, their area can be subtracted from the total wall area to get a more accurate estimate, especially for large openings. However, for pattern matching, you still need full drops above and below openings, so this subtraction is often more relevant for plain wallpapers or very large openings. Our calculator primarily focuses on drops needed, which inherently accounts for pattern matching around openings.
How to Measure Your Room
- Measure Wall Height: Measure from the top of your baseboard to the ceiling. Take several measurements around the room and use the tallest one to ensure you have enough length for every strip.
- Measure Total Wall Length (Perimeter): Measure the length of each wall and add them together. Alternatively, measure the perimeter of the room.
- Measure Doors and Windows (Optional): If you want to subtract these areas, measure their height and width to calculate their total area.
Using the Wallpaper Roll Calculator
Our calculator simplifies the process by asking for the following inputs:
- Total Wall Length: The sum of all wall lengths in the room.
- Wall Height: The height from floor to ceiling.
- Wallpaper Roll Width: Found on the wallpaper packaging.
- Wallpaper Roll Length: Also found on the wallpaper packaging.
- Pattern Repeat Length: The distance at which the pattern repeats, specified on the roll label. Enter '0' if your wallpaper has no pattern.
- Extra for Waste/Cuts (%): A percentage buffer for errors and trimming.
- Area of Doors/Windows to Subtract: The combined area of any large openings you wish to exclude from the total wall area calculation.
The calculator will then provide you with the recommended number of rolls to purchase, ensuring you have enough to complete your project with confidence.
Example Calculation
Let's say you have a room with a total wall length of 1500 cm (15 meters) and a wall height of 250 cm. Your wallpaper rolls are 53 cm wide and 1000 cm long, with a pattern repeat of 53 cm. You want to add 10% for waste.
- Total Wall Length: 1500 cm
- Wall Height: 250 cm
- Roll Width: 53 cm
- Roll Length: 1000 cm
- Pattern Repeat: 53 cm
- Waste Percentage: 10%
The calculator would determine that each drop needs to be 318 cm long (to accommodate the 53 cm pattern repeat over a 250 cm wall height, requiring 6 repeats of 53 cm). From a 1000 cm roll, you'd get 3 drops. To cover 1500 cm of wall with 53 cm wide strips, you'd need 29 drops. This would translate to approximately 10 rolls, rounded up to ensure you have enough.