Cubic yards, tons, and coverage for river rock projects. Enter your area dimensions and depth.
Enter area, depth, and rock type.
Add 10% for irregular shapes and settling.
River rock is the most popular decorative landscape stone — smooth, rounded stones ranging from 1 to 5 inches in diameter, shaped by water erosion. It's used for dry creek beds, borders, ground cover, and drainage. River rock weighs approximately 2,700 lb per cubic yard (1.35 tons), making it one of the heavier landscape materials to work with.
Enter your area dimensions and depth above. As a quick reference: 100 sq ft at 3 inches deep needs about 0.93 cubic yards or 1.25 tons. At $75/ton delivered, that's roughly $94 in material. The bigger the rock size, the deeper you need to go — 3-inch river rock should be laid at least 3–4 inches deep to avoid bare spots.
1–2 inch for ground cover and garden beds. 2–3 inch for borders and dry creek beds. 3–5 inch for drainage channels and erosion control. Larger rocks are more stable but create more gaps between stones. For a smooth, walkable surface, use smaller sizes (1–2 inch).
River rock doesn't decompose like mulch, so a one-time installation lasts decades. However, it migrates without edging — install steel or plastic landscape edging around river rock beds. Use landscape fabric underneath to prevent rocks from sinking into the soil. And plan for the weight: a typical project uses 2–5 tons, which means delivery and placement equipment, not bags from a home center.