River Rock Calculator
Estimate the volume and weight of river rock needed for landscaping, drainage, and decorative projects.
Quick Answer
To calculate river rock, multiply length × width × depth in feet, divide by 27 for cubic yards, then multiply by about 1.45 for tons. River rock weighs roughly 1.4–1.5 tons per cubic yard, and one ton covers about 70–100 sq ft at 2 inches deep.
River Rock Calculator Guide
The river rock calculator helps you determine the exact volume and weight of river rock needed for landscaping, drainage, and decorative projects. River rock offers unique aesthetic appeal while providing functional benefits for erosion control and water feature design.
River rock comes in various sizes from 1-2 inches to larger decorative stones. This calculator accounts for material type and density to provide accurate volume estimates in cubic yards and weight in tons. For complementary materials, you may also need our pea gravel calculator or stone coverage calculator for layered landscaping designs.
River rock is ideal for pond edging, water features, stream beds, and decorative landscaping. Its rounded shape prevents sharp edges while providing excellent drainage for low-lying areas. The calculator helps you estimate both decorative river rock for surface coverage and bulk quantities for structural applications like drainage systems or foundation stabilization.
River rock coverage by depth (approx., ~1.45 tons per cubic yard):
| Depth | Coverage per ton | Coverage per cubic yard |
|---|---|---|
| 2" | ≈ 90 sq ft | ≈ 130 sq ft |
| 3" | ≈ 60 sq ft | ≈ 87 sq ft |
| 4" | ≈ 45 sq ft | ≈ 65 sq ft |
How Many Tons in a Cubic Yard of River Rock?
River rock weighs about 1.45 tons per cubic yard, so one cubic yard is roughly 1.45 tons (2,900 lb). Larger, denser rock weighs a little more per yard.
How Many Cubic Yards in a Ton of River Rock?
About 0.69 cubic yards (1 ÷ 1.45). A 5-ton load is roughly 3.4 cubic yards. Convert any amount with the cubic yards to tons calculator.
Sources & Methodology
Volume-to-weight results use standard aggregate bulk densities (for example, crushed stone ≈ 1.5 US tons per cubic yard) applied consistently across this site, and pricing reflects 2026 U.S. supplier averages that vary by region and delivery. All results are planning estimates — confirm the exact density and price with your local supplier before ordering.
Lay River Rock So It Stays Put and Weed-Free
River rock's rounded shape is what makes it drain well — and also what makes it sink into bare soil and scatter if it's not set up right. A heavy-duty landscape fabric underneath gives the rock a stable mat to sit on, stops it from disappearing into the dirt, and blocks weeds from growing up between the stones. And because river rock is dense and heavy, a sturdy contractor wheelbarrow is genuinely worth it for moving it from the pile to the bed without wearing yourself out.
Heavy-Duty Landscape Fabric
Gives rounded rock a stable base so it won't sink into soil, and blocks weeds below.
Check Price on AmazonContractor Wheelbarrow
Moves heavy, dense river rock from the pile to the bed without the back strain.
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Frequently Asked Questions
How much river rock do I need?
Measure your project area's length, width, and desired depth in feet. Multiply to get cubic feet, then divide by 27 for cubic yards. A 10×10 ft area at 3 inches deep needs approximately 0.93 cubic yards. Our calculator automates this process for any size project.
What is river rock best used for?
River rock is excellent for water features and ponds (due to its smooth surface), decorative landscaping borders, erosion control on slopes, and accent areas in gardens. Its rounded shape makes it more decorative than functional compared to angular crushed stone, so use it where aesthetics matter.
How much does river rock weigh per cubic yard?
River rock typically weighs 1.4-1.5 tons per cubic yard, depending on size and moisture content. Larger stones weigh more per volume than smaller decorative river pebbles. The calculator provides weight estimates based on the specific type and size of river rock you select.
Can river rock be used for driveway base?
Not recommended. River rock's rounded shape doesn't compact well or interlock, making it unstable for driveways or load-bearing applications. Use angular crushed stone for bases. River rock is best reserved for decorative and low-load applications.
How deep should river rock be for landscaping?
For decorative applications, 2-3 inches is standard. For water feature edging or accent areas, 3-4 inches provides better coverage and visual impact. For erosion control on slopes, 4-6 inches may be needed depending on soil stability. Adjust depth in the calculator to see coverage at different depths.