River Rock Calculator
Tons and yards of decorative stone — sized to your bed, not the guess at the yard.
Your bed
Materials list
Generated by AllUnits.io — allunits.io/calculators/river-rock
How this calculator figures it
Volume is area × depth in cubic yards; tonnage uses 1.4 tons per cubic yard, the midpoint of published river-rock densities (1.3–1.5 depending on stone size and moisture). Coverage cross-check: one ton spreads over roughly 90–100 square feet at a 2-inch depth.
How it works
Worked example — a 15 × 4 ft border at 3 inches: 60 sq ft × 3 ÷ 12 = 15 cu ft = 0.56 yd³, about 0.8 tons of 1–3 inch river rock. One ton covers roughly 90–100 sq ft at a 2-inch depth.
River rock FAQs
How deep should river rock be?
At least 2 inches for coverage; for stones larger than 2 inches, go about twice the stone diameter.
How much does a ton cover?
About 90–100 sq ft at 2 inches for 1–2 inch rock.
Should I put fabric underneath?
Common practice under decorative rock to keep soil and rock separate and slow weeds.
Rock or mulch?
Rock is permanent and low-maintenance but holds heat and doesn't feed soil; mulch is cheaper up front and better for plantings.
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Related calculators & sources
Functional stone and bases: Gravel Calculator. Organic cover instead: Mulch Calculator. Densities are cited at aggregate density charts; convert measurements with the weight and area converters.
Estimates for planning and purchasing. Not engineering or code-compliance advice — confirm structural work with your local building department.