Crushed Stone (approx. 2500 lbs/yd³)
Pea Gravel (approx. 2800 lbs/yd³)
River Rock (approx. 3000 lbs/yd³)
Sand (approx. 2700 lbs/yd³)
Understanding Gravel Calculations
Calculating the amount of gravel needed for a project is crucial for effective planning and budgeting. This calculator helps you determine the volume and estimated cost of gravel required for a specific area. Gravel is typically measured and sold by the cubic yard (yd³).
How it Works:
The calculator follows these steps:
Calculate Area: The length and width of your project area are multiplied to find the total square footage (Area = Length × Width).
Convert Depth to Feet: The desired depth, often given in inches, is converted into feet by dividing by 12 (Depth in feet = Depth in inches / 12).
Calculate Volume in Cubic Feet: The area in square feet is multiplied by the depth in feet to get the total volume in cubic feet (Volume in cubic feet = Area × Depth in feet).
Convert Volume to Cubic Yards: Since gravel is sold by the cubic yard, the volume in cubic feet is divided by 27 (there are 27 cubic feet in 1 cubic yard) (Volume in yd³ = Volume in cubic feet / 27).
Estimate Total Weight (Optional but useful for ordering): Some suppliers may refer to gravel by weight. The volume in cubic yards is multiplied by the typical density of the selected gravel type (usually in pounds per cubic yard).
Calculate Total Cost: The volume in cubic yards is multiplied by the cost per cubic yard to estimate the total material cost.
Construction: Base material for patios, foundations, retaining walls, drainage systems.
Erosion Control: Stabilizing slopes and preventing soil runoff.
Important Considerations:
Compaction: Gravel will compact over time, especially under weight. It's often recommended to order slightly more (5-10%) than your initial calculation to account for this.
Coverage: Different gravel types have slightly different densities. The calculator uses approximate typical densities for common types. Always check with your supplier for exact specifications.
Delivery Fees: The cost calculated here is for the material only. Delivery charges may apply and can significantly impact the total project cost.
function calculateGravel() {
var length = parseFloat(document.getElementById("length").value);
var width = parseFloat(document.getElementById("width").value);
var depthInches = parseFloat(document.getElementById("depth").value);
var gravelTypeDensity = parseFloat(document.getElementById("gravelType").value);
var costPerCubicYard = parseFloat(document.getElementById("costPerCubicYard").value);
var resultDiv = document.getElementById("result");
resultDiv.innerHTML = "; // Clear previous results
if (isNaN(length) || isNaN(width) || isNaN(depthInches) || isNaN(costPerCubicYard) || length <= 0 || width <= 0 || depthInches <= 0 || costPerCubicYard < 0) {
resultDiv.innerHTML = "Please enter valid positive numbers for dimensions and cost.";
return;
}
// 1. Calculate Area in square feet
var areaSqFt = length * width;
// 2. Convert depth from inches to feet
var depthFt = depthInches / 12;
// 3. Calculate Volume in cubic feet
var volumeCubicFt = areaSqFt * depthFt;
// 4. Convert Volume to cubic yards
var volumeCubicYards = volumeCubicFt / 27;
// 5. Estimate Total Weight (optional, but good to know)
var totalWeightLbs = volumeCubicYards * gravelTypeDensity * 2000; // Convert tons (if density is in tons/yd³) to lbs, or adjust if density is already in lbs/yd³
// The values in the select are densities in Tons per Cubic Yard.
// Example: 0.025 for crushed stone means 2500 lbs per cubic yard is approximately 1.25 tons.
// Let's re-evaluate the select values to be more standard lbs/yd³.
// Standard densities:
// Crushed Stone: ~2700 lbs/yd³
// Pea Gravel: ~2600 lbs/yd³
// River Rock: ~2700 lbs/yd³
// Sand: ~2700-3000 lbs/yd³
// Let's update the select values to be more representative densities in lbs/yd³
var selectedGravelType = document.getElementById("gravelType");
var selectedDensity;
switch(selectedGravelType.value) {
case "crushed": selectedDensity = 2700; break; // lbs/yd³
case "pea": selectedDensity = 2600; break; // lbs/yd³
case "river": selectedDensity = 2700; break; // lbs/yd³
case "sand": selectedDensity = 2850; break; // lbs/yd³
default: selectedDensity = 2700; // Default to crushed stone
}
// Re-writing this part to use the updated switch logic and densities
var volumeCubicYards = volumeCubicFt / 27;
var totalWeightLbs = volumeCubicYards * selectedDensity;
// 6. Calculate Total Cost
var totalCost = volumeCubicYards * costPerCubicYard;
// Format results
var formattedVolume = volumeCubicYards.toFixed(2);
var formattedWeight = totalWeightLbs.toFixed(0);
var formattedCost = totalCost.toLocaleString('en-US', { style: 'currency', currency: 'USD' });
resultDiv.innerHTML = `
Estimated Gravel Needed:
${formattedVolume} cubic yards
Approximately ${formattedWeight} lbs
Estimated Material Cost:
${formattedCost}
`;
}