Decomposed Granite Calculator
Calculate decomposed granite (DG) for paths, patios and beds from your measurements, with optional weight from your supplier's bulk density.
Result
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Your result will appear here
Enter your measurements and calculate to see volume in cubic yards, cubic feet, and cubic metres.
How this calculator works
The calculator multiplies your area by the finished depth of DG you want, then converts the result to cubic yards, cubic feet and cubic metres.
Volume = Area × Finished depth
This is the volume of the finished layer. The calculator does not apply a compaction adjustment for DG.
About decomposed granite
Decomposed granite — often called DG — is granite that has weathered into small particles and fines. It is used for paths, patios, and the spaces between plants and pavers.
Finished depth versus what to order
DG is often compacted in place, and some products are stabilized. How much loose DG you need for a given finished depth depends on the product and installation. Ask your supplier or installer how much to order for your finished depth; you can add a percentage as an Extra material / handling allowance if they suggest one.
Bag labels are not bulk density
We found no reliable general bulk density for DG. A bag that lists both a weight and a nominal volume does not tell you the density of loose stockpiled DG, so weight here uses only the bulk density your supplier gives for the product.
Planning several beds and paths? Use the Landscape Rock Calculator. For other materials, use the Gravel Calculator.
Worked example
Example: 12 ft × 12 ft patio at 3 in finished depth
- Area: 12 ft × 12 ft = 144 ft²
- Depth: 3 in = 0.25 ft
- Volume: 144 × 0.25 = 36.0 ft³
- Cubic yards: 36.0 ÷ 27 = 1.33 yd³
Result: 1.33 cubic yards (1.02 cubic metres) of finished DG. The depth is an example input.
Frequently asked questions
How much extra DG should I order for compaction?
It depends on the product and how it is installed. Ask your supplier or installer; if they give you a percentage, enter it as the Extra material / handling allowance.
How much does a cubic yard of DG weigh?
We found no reliable general figure. Enter the bulk density your supplier gives for the product to get an estimated weight.
Can I use the bag weight to work out bulk density?
Not reliably. A bag’s stated weight and nominal volume do not establish the density of loose, stockpiled DG.
Sources & methodology
Volume is geometry plus unit conversion. Sources relevant to this page:
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NIST Guide to the SI (SP 811), Appendix B.8 — Factors for units listed alphabetically
Used in calculations: Length conversion constants used in every calculation.
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ASTM C29/C29M-17a — Standard Test Method for Bulk Density (“Unit Weight”) and Voids in Aggregate
Methodology only: Explains that bulk density includes the spaces between particles and differs between loose and compacted conditions.