Landscape Rock Calculator
How much river rock, pebbles or decorative stone to buy for a bed or border, in tons, cubic yards and bags.
Volume
- Cubic yards
- 0.56 cu yd
- Cubic feet
- 15 cu ft
- Weight
- 1,575 lb
Bags
- 0.5 cu ft bags
- 30 bags
Bed
- Area covered
- 60 sq ft
Cost
- Estimated cost
- –
How much landscape rock do I need?
Multiply the bed's area in square feet by the depth in feet (inches ÷ 12), divide by 27 for cubic yards, then multiply by about 1.42 tons per cubic yard. A 15 × 4 ft bed 3 inches deep needs 0.56 cubic yards, about 0.79 tons or 30 bags of 0.5 cu ft.
Worked example: a 15 × 4 ft rock bed, 3 inches deep
- Area: 15 × 4 = 60 sq ft.
- Volume: 60 × 0.25 ft = 15 cu ft = 0.56 cu yd.
- Weight: at about 105 lb per cu ft, that's 0.79 tons (1,575 lb).
- Bags: 15 ÷ 0.5 = 30 bags.
How far landscape rock goes
Area covered by one 0.5 cu ft bag, one cubic yard and one ton (at 1.42 tons per cubic yard).
| Depth | 0.5 cu ft bag | 1 cubic yard | 1 ton |
|---|---|---|---|
| 2 in | 3 sq ft | 162 sq ft | 114 sq ft |
| 3 in | 2 sq ft | 108 sq ft | 76 sq ft |
| 4 in | 1.5 sq ft | 81 sq ft | 57 sq ft |
Choosing a depth
The bigger the stones, the deeper the layer needs to be to cover the ground or landscape fabric without gaps. Small pebbles look full at about 2 inches; larger river rock usually needs 3 inches or more. If you can see fabric between the stones, add more.
Bags or bulk
Decorative stone is sold in bags of about 0.5 cu ft, roughly 50 lb each. That's fine for a tree ring or a small border. For anything over about half a cubic yard, a landscape yard selling by the ton is usually much cheaper. Rock is heavy: a cubic yard weighs about 2,800 lb, more than many pickups can carry.
Before you order
- Lay landscape fabric under the rock to slow weeds and stop the stones sinking into the soil.
- Edge the bed so rock doesn't spread into the lawn.
- Ask for the supplier's weight figure if you buy by the ton. Weights vary by stone, and "My supplier's figure" uses theirs.
- Compare with gravel: for paths and driveways, the gravel calculator adds an allowance for compaction.
Frequently asked questions
How much area does a ton of river rock cover?
How many bags of landscape rock do I need?
How much does a cubic yard of river rock weigh?
How many bags of rock are in a cubic yard?
Guides
Related calculators
Sources and method
- Engineering ToolBox — densities of dirt, sand, gravel and other materials — gravel, dry 105 lb/ft³ (used as the typical rock weight)
- Vigoro 0.5 cu ft Bagged Decorative Landscape Rock (Home Depot) — bag size
Last checked October 12, 2026. How we build and test every calculator: methodology.