River Rock Calculator
Enter the area and depth of your bed to estimate how much river rock you need in cubic yards and tons, plus the number of bags.
Results
- Volume needed
- 1.23 cu yd
- With 10% waste
- 1.36 cu yd
- Cubic feet
- 33.33 cu ft
- Cubic meters
- 0.94 m³
- Estimated weight
- 1.9 tons
- 0.5 cu ft bags
- 74 bags
Estimates only. Round up and buy a little extra to account for waste, spills, and breakage.
River rock is smooth and rounded, sold by the ton, and covers less ground per ton than crushed stone because the stones nest loosely.
This calculator reports cubic yards and tons so you can order from a bulk yard without guessing the conversion.
Also works as a river stone calculator, river rock coverage calculator, and dry creek bed estimator.
How to use the river rock calculator
- Enter the shape.
- Enter the length in ft.
- Enter the width in ft.
- Enter the depth in in.
- Enter the waste factor in %.
- Optionally add a price to estimate the total project cost.
- Read your quantities instantly — no sign-up, and you can print the estimate to take to the supplier.
Worked example
Inputs
- Shape
- Rectangle / Square
- Length
- 20 ft
- Width
- 10 ft
- Depth
- 2 in
- Waste factor
- 10 %
Results
- Volume needed
- 1.23 cu yd
- With 10% waste
- 1.36 cu yd
- Cubic feet
- 33.33 cu ft
- Cubic meters
- 0.94 m³
- Estimated weight
- 1.9 tons
- 0.5 cu ft bags
- 74 bags
Using the example values above, the river rock calculator returns 1.23 cu yd (volume needed). Change any field to match your own project and the numbers update instantly.
River rock coverage by size
At 2 inches deep, one ton of 1 inch river rock covers about 100 square feet. Larger 3 to 5 inch rock covers closer to 60 to 70 square feet per ton.
For dry creek beds, plan 3 to 4 inches of depth and mix sizes so the bed looks natural rather than uniform.
How much extra should I order?
Always order a little extra. A 5% waste factor suits simple, square projects; 10% is right for most jobs; bump it to 15–20% for irregular shapes, diagonal patterns, or uneven ground. Running short almost always costs more than the leftover material.
Weight per cubic yard
| Material | Tons per cu yd |
|---|---|
| Crushed stone / gravel | 1.4 |
| Pea gravel | 1.4 |
| Sand (dry) | 1.35 |
| River rock | 1.3 |
| Topsoil (moist) | 1.1 |
Formula
Volume (cu ft) = area × depth ÷ 12. Cubic yards = cu ft ÷ 27. Waste-adjusted = volume × (1 + waste%).
Frequently asked questions
- How deep should river rock be?
- Spread river rock 2–3 inches deep for ground cover and 3–4 inches over a drainage trench or weed barrier.
- How many tons of river rock do I need?
- Multiply the area by the depth in feet to get cubic feet, divide by 27 for cubic yards, then multiply by about 1.4 to get tons.
- How much does a yard of river rock weigh?
- Roughly 1.25 to 1.35 tons depending on stone size and moisture content.
- How deep should river rock be?
- 2 inches for decorative beds and 3 to 4 inches for drainage swales and dry creek beds.
Related calculators
Pea Gravel Calculator
Estimate tons and cubic yards of pea gravel for paths and patios.
Gravel Calculator
Find tons and cubic yards of gravel or crushed stone for driveways and paths.
Landscape Rock Calculator
Estimate tons and cubic yards of decorative landscape rock.
Stone Calculator
Estimate tons and cubic yards of crushed or decorative stone.