River Rock Calculator
Calculate tons of river rock for beds, dry creek beds and drainage.
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Currency: Amounts are calculated in the currency you select; this site does not convert between currencies and does not use live exchange rates.
What this tool does
The River Rock Calculator estimates the cubic yards and tons of river rock for a decorative bed or dry creek, using a typical density for 1–3 inch rock.
How to use the River Rock Calculator
- Measure the length and width of the area.
- Enter the depth you want to fill.
- Choose the material so the correct density is used.
- Enter your supplier's price per ton.
- Order the volume or tonnage shown, rounded up.
Formula
yd³ = L × W × (D ÷ 12) ÷ 27; tons = yd³ × density ÷ 2,000
- L, W
- Length and width in feet
- D
- Depth in inches
- density
- Material weight in lb per cubic yard
Densities are typical loose values; moisture and gradation change actual weight by ±10%.
Worked example
A 20 × 10 ft area filled 3 in deep with river rock (1–3 in).
Inputs
- Length20 ft
- Width10 ft
- Depth3 in
- MaterialRiver rock (1–3 in) (2,600 lb/yd³)
- Price per ton$90
Result
- Volume needed1.85 cu yd
- Weight2.41 US tons
- Volume50 cu ft
- Area covered200 sq ft
- Estimated cost$216.67
Material density (per cubic yard)
| Material | Weight | US tons |
|---|---|---|
| River rock (1–3 in) | 2,600 lb | 1.30 tons |
Results explained
- Volume needed
- Cubic yards to order (how most yards sell bulk material).
- Weight
- Tons, for quarries that sell by weight and to check truck capacity.
- Volume (cu ft)
- Same volume in cubic feet, useful for bagged products.
- Area covered
- Surface area of the bed or base.
- Estimated cost
- Tons × your price per ton, before delivery.
Frequently asked questions
2–3 inches for 1–3 in rock; use roughly twice the rock diameter for full coverage.
About 100 sq ft at 2 inches deep.
About 2,600 lb (1.3 tons).
Landscape fabric reduces weeds and keeps rock from sinking into soil.
Yes — it's commonly used in dry creek beds and around downspouts.