A topsoil calculator is an easy way to add soil or mulch to garden plots. Many home improvement chains offer free topsoil and mulch calculation tools on their official websites to help customers estimate how much soil or mulch they need for their outdoor spaces. To use these basic tools, run through the following steps.
Find a topsoil calculator online. For example, both The Home Depot and Lowe's offer topsoil and mulch calculators.
Multiply the length and the width of the space to calculate square yardage.
Enter the desired depth of the soil or mulch into the calculator.
Choose the desired material type, such as topsoil, wood mulch, rubber mulch, straw or pine needles.
Select the calculate option to determine the amount of topsoil or mulch. The tool then calculates the volume of soil required to fill the space. Some calculators, such as the Lowe's calculator, also offer an option to calculate the amount by bags, bales or truckloads.