River rock calculator

Estimate river rock for drainage, beds and dry creek beds. Returns yards, tons, bags and cost.

Short answer: cu yd = (L × W × depth/12) ÷ 27. Tons = cu yd × 1.45. Small bag ≈ 0.5 cu ft. 15 × 4 ft × 3" = 15 cu ft ≈ 0.56 cu yd ≈ 0.8 tons = 30 bags. Enter your measurements above and the river rock calculator returns the quantity, unit conversions and an estimated cost instantly, in imperial or metric — no sign-up needed.

What do you need to measure?

What is the answer?

Cubic yards
0.56
Tons
0.81
≈ 1.45 t/yd³
0.5 cu ft bags
30
$73

How does the river rock calculator work?

cu yd = (L × W × depth/12) ÷ 27. Tons = cu yd × 1.45. Small bag ≈ 0.5 cu ft.

What does a worked example look like?

15 × 4 ft × 3" = 15 cu ft ≈ 0.56 cu yd ≈ 0.8 tons = 30 bags.

What do people ask most?

How many bags of river rock in a cubic yard?

About 54 bags of 0.5 cu ft equal one cubic yard.

How deep for drainage?

4–6" over landscape fabric for a French drain or dry creek bed.

Which yard & landscape calculator should you use next?

Where can you learn more?

Read field notes on estimating and materials, or browse every calculator we make.