How the river rock calculation works

Measure the project area and choose a finished depth. The calculator converts that volume to cubic yards, then uses the selected planning density to estimate weight. Add an extra-material allowance for uneven grade, settling and spillage.

River rock density planning values

River rock weight varies with stone size, moisture and supplier. The presets are planning values only. If your supplier provides a product-specific density, choose Custom density and enter that figure before ordering.

How deep should river rock be?

Decorative beds often use a few inches of rock, while larger stones and dry creek features may need a deeper layer. Match depth to the stone size and project purpose, and follow supplier or contractor recommendations for drainage or engineered applications.

QUICK ANSWERS

Common questions

How many tons of river rock do I need?

Calculate cubic yards from the area and depth, then multiply by the supplier’s weight per cubic yard. The calculator does this automatically and also shows metric tonnes.

How much area does one cubic yard cover?

One cubic yard is 27 cubic feet. It covers about 162 sq ft at 2 inches deep, 108 sq ft at 3 inches, or 81 sq ft at 4 inches before extra material.

Can I calculate bags and cost?

Yes. Enter the bag volume printed on the product and your supplier price. For bulk purchases, use price per ton or cubic yard.