How to Calculate and Use Mulch
Calculating the right amount of mulch or topsoil is the first step to any successful landscaping project. It helps you budget accurately and avoid waste. This calculator uses simple geometry to find the volume you need.
Step 1: Find Your Area (Square Feet)
First, determine the basic shape of your garden bed. For squares and rectangles, multiply Length x Width. For circles, the formula is π x Radius². For triangles, it's ½ x Base x Height. This gives you the total area in square feet.
Step 2: Calculate Volume (Cubic Feet)
Once you have the square footage, you need to account for the depth. Since depth is usually measured in inches, you must first convert it to feet by dividing by 12. Then, multiply your area by the depth in feet. The formula is: Area (sq ft) x (Depth (in) / 12) = Volume (cu ft).
Step 3: Convert to Cubic Yards or Bags
Bulk materials like mulch and soil are typically sold by the cubic yard. There are 27 cubic feet in one cubic yard. If you prefer to buy in bags, they are usually sold in 2 or 3 cubic foot sizes. Our calculator provides all these conversions for you automatically.