Jumbo (10″ x 7″)
Standard (9″ x 5″)
Landscape (8″ x 4″)
Cube (4″ x 4″)
Total Area:0 sq ft
Estimated Stones Needed:0
Stones (Including Waste):0
Estimated Material Cost:$0.00
How to Calculate Cobblestone Quantity
Planning a cobblestone driveway or Belgian block path requires precision to avoid mid-project supply runs or excessive leftover waste. This calculator determines the total number of stones based on your square footage and the specific dimensions of the stone type chosen.
Understanding Standard Sizes
Jumbo: Approximately 10″ x 7″ x 4″. Ideal for driveways and heavy-traffic borders.
Standard: Approximately 9″ x 5″ x 5″. The classic choice for traditional European-style streets.
Landscape: Approximately 8″ x 4″ x 4″. Perfect for garden paths and decorative edging.
Cubes: Approximately 4″ x 4″ x 4″. Often used for intricate patterns like fans or circles.
The Importance of Joint Width
The "Joint Width" is the gap between each stone that will be filled with sand, polymeric sand, or mortar. Even a 0.5-inch gap significantly changes the total stone count over a large area. Our calculator factors this into the footprint of each stone to provide a realistic estimate.
Practical Example
If you have a path that is 20 feet long and 3 feet wide (60 sq ft) and you are using Jumbo blocks (10″x7″) with a 0.5-inch joint:
Adjust stone size for joints: 10.5″ x 7.5″ = 78.75 square inches per stone.
Convert to square feet: 78.75 / 144 = 0.546 sq ft per stone.
Calculate base count: 60 / 0.546 = 110 stones.
Add 10% waste: 110 + 11 = 121 stones total.
Pro Installation Tip
Always order a waste factor of at least 10%. Cobblestones are natural products; some may arrive chipped, or you may need to cut stones to fit the edges of your layout. For circular or curved patterns, increase the waste factor to 15%.
function calculateCobbles() {
var length = parseFloat(document.getElementById('projLength').value);
var width = parseFloat(document.getElementById('projWidth').value);
var stoneDim = document.getElementById('stoneSize').value.split(',');
var sL = parseFloat(stoneDim[0]);
var sW = parseFloat(stoneDim[1]);
var joint = parseFloat(document.getElementById('jointWidth').value);
var waste = parseFloat(document.getElementById('wasteFactor').value);
var unitCost = parseFloat(document.getElementById('costPerStone').value);
if (isNaN(length) || isNaN(width) || length <= 0 || width 0) {
var totalCost = totalWithWaste * unitCost;
document.getElementById('resCost').innerText = "$" + totalCost.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
costRow.style.display = 'flex';
} else {
costRow.style.display = 'none';
}
document.getElementById('cobble-results').style.display = 'block';
}