Landscape Rock Calculator

Calculate how much decorative river rock, lava rock, or landscape stone you need by area and depth.

Circle uses length as the diameter; width is ignored.

5% simple, 10% normal, 15% irregular, 20% complex.

Leave at 0 to skip the cost estimate.

Results

Volume needed
0.99 cu yd
With 10% waste
1.09 cu yd
Cubic feet
26.67 cu ft
Cubic meters
0.76 m³
Estimated weight
1.41 tons

Estimates only. Round up and buy a little extra to account for waste, spills, and breakage.

Calculate how much decorative river rock, lava rock, or landscape stone you need by area and depth.

How to use the landscape rock calculator

  1. Enter the shape.
  2. Enter the length in ft.
  3. Enter the width in ft.
  4. Enter the depth in in.
  5. Enter the waste factor in %.
  6. Optionally add a price to estimate the total project cost.
  7. 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
8 ft
Depth
2 in
Waste factor
10 %

Results

Volume needed
0.99 cu yd
With 10% waste
1.09 cu yd
Cubic feet
26.67 cu ft
Cubic meters
0.76 m³
Estimated weight
1.41 tons

Using the example values above, the landscape rock calculator returns 0.99 cu yd (volume needed). Change any field to match your own project and the numbers update instantly.

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.

Formula

Volume (cu ft) = area × depth ÷ 12. Cubic yards = cu ft ÷ 27. Waste-adjusted = volume × (1 + waste%).

Frequently asked questions

How deep should landscape rock be?
Use 2–3 inches over fabric for full ground coverage.
Should I use fabric under rock?
Yes, landscape fabric suppresses weeds and keeps rock from sinking into soil.

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