Estimate decorative rock by volume and editable supplier density without assuming every rock weighs the same.
Use this calculator to plan decorative rock by volume and then estimate its weight from the material density you enter. It is useful when a supplier sells by cubic yard, ton, or bag and you want to compare the same measured area.
Net area multiplied by depth gives volume. Volume in cubic yards multiplied by material density gives estimated tons.
A 432 sq ft planting strip at 3 inches is 108 cu ft, or 4 yd³. Enter the product density to turn that volume into a more useful delivery estimate.
Bring the product name or a sample to the supplier and ask how it is sold by yard, ton, or bag. Confirm whether it is delivered loose and how the load will reach the planting area.
Rock shape, gradation, voids, density, bag fill, and settling vary by product. Use the supplier's values instead of treating a typical density as a product specification.
The calculator does not specify landscape fabric, edging, base preparation, drainage, or the final depth needed for a particular installation.
Start with volume from your measured area. Use the weight estimate only after you confirm the density or selling unit with the supplier.
It can change density and how much space is left between pieces. Use the product information and treat the result as a planning estimate.
The tool applies one depth to a measured area. A slope or changing depth may need separate sections and a local check.
Short, practical help for the next step in this project.