Rock Calculator
Estimate how much landscape rock or river rock you need by cubic yards and tons for beds, borders, and ground cover.
Quick Answer
To estimate landscape rock, multiply length × width × depth in feet, divide by 27 for cubic yards, then multiply by about 1.4–1.5 for tons. One ton of rock covers roughly 70–100 sq ft at 2 inches deep, with larger stone covering less.
Rock Calculator (Landscape Rock by Yard & Ton) Guide
The rock calculator tells you exactly how much landscape rock to order—in cubic yards and tons—for beds, borders, dry creek beds, and decorative ground cover. Enter the area's length, width, and the depth you want, and it converts everything for you so you don't end up short or with a leftover pile.
How Much Rock Do You Need?
Multiply length × width × depth (in feet), then divide by 27 for cubic yards. Most landscape rock weighs about 1.3–1.5 tons per cubic yard, so multiply your cubic yards by roughly 1.4 for a tonnage order. Depth depends on rock size: 2 inches is enough for small decorative stone, while larger river rock and cobbles need 3–4 inches for full coverage.
Choosing the Right Landscape Rock
Smooth river rock suits water features and borders; lightweight lava rock is great for low-weight beds; and angular crushed rock locks together for paths and driveways. For smaller, finer cover, compare options with our decorative stone calculator or plan a whole yard with the landscape stone calculator.
How Many Tons in a Cubic Yard of Rock?
Landscape rock weighs about 1.4 tons per cubic yard, so one cubic yard is roughly 1.4 tons. Larger, denser stone runs closer to 1.5 tons, while lightweight lava rock is far less (about 0.8 tons).
Rock coverage per ton by size (at 2 inches deep):
| Rock size | Coverage per ton |
|---|---|
| Small (½–1½ in) | ≈ 100–120 sq ft |
| Medium (1½–3 in) | ≈ 80–100 sq ft |
| Large (3–5 in) | ≈ 60–80 sq ft |
| Very large (6 in+) | ≈ 25–50 sq ft |
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.
Frequently Asked Questions
How much area does a ton of landscape rock cover?
At a 3-inch depth, one ton of rock covers roughly 70–90 square feet, since a ton is about 0.7 cubic yards. Spread thinner at 2 inches, the same ton covers closer to 110–130 square feet. Larger rock and deeper coverage reduce the area per ton.
How deep should landscape rock be?
For small decorative stone, 2 inches gives full coverage. For larger river rock or in high-traffic areas, use 3–4 inches. Laying a weed barrier fabric underneath keeps the rock clean and stops it sinking into the soil.
How much does a cubic yard of rock weigh?
Most landscape rock weighs about 2,600–3,000 pounds per cubic yard (1.3–1.5 tons). Denser river rock sits at the heavier end, while porous lava rock is much lighter at roughly 1,500 pounds per cubic yard.
What is the difference between rock and gravel?
Gravel is small (typically under 1 inch) and often used for paths and bases, while landscape rock covers a wider range of larger decorative stones like river rock and cobbles. Both are estimated the same way—by area and depth.