How this calculator works
It calculates the volume from your area and depth, converts to cubic yards, then to tons using a typical river rock weight of about 1.4 tons per cubic yard.
Worked example — a 15 ft × 10 ft bed at 2 inches:
150 × (2 ÷ 12) = 25 cubic feet → ÷ 27 = 0.93 cubic yards → about 1.3 tons.
150 × (2 ÷ 12) = 25 cubic feet → ÷ 27 = 0.93 cubic yards → about 1.3 tons.
How deep for river rock?
A 2-inch layer covers the ground for decorative beds; go 3–4 inches for drainage areas or to fully hide landscape fabric.
Frequently asked questions
How many tons of river rock per cubic yard?
About 1.4 tons, similar to gravel.
How deep should river rock be?
2 inches for decoration, 3–4 inches for drainage or coverage.