Convert planting bed square footage and coverage depth into yards, tons, bags, and cost.
Tools to have ready
- Tape measure
- Garden hose or marking paint
- Graph paper
- Depth ruler
How to take the measurements
Trace the bed edge with hose or paint.
Break curved beds into rectangles, triangles, and circles.
Add those areas to get total square feet.
Choose a rock size and starting depth.
Increase waste for curves and border trimming.
Landscape-bed coverage
- 1Rock layer
- 2Specified depth
- 3Landscape fabric
- 4Measured bed area
How the calculator works
Volume = bed area x coverage depth.
Example: a 200 sq ft bed at 2 inches deep needs about 1.23 cubic yards before waste.
What every field and unit means
Measured bed area
Total surface area to cover with decorative rock.
Unit: sq ft or m2. Measure or sketch the bed and add simple shapes.Rock-size preset
Adjusts the starting depth for coverage by rock size.
Choose larger rock when pieces need a deeper layer to cover soil.Coverage depth
Average finished rock depth.
Unit: in or cm. Measure from soil or fabric up to the finished rock surface.Rock density
Bulk density of the decorative rock.
Unit: lb/ft3 or kg/m3. Use supplier tons per yard for the chosen product.Extra / waste
Percent added for cuts, spillage, edge cleanup, and small estimating errors.
Unit: percent. Use 5 percent for simple square work and 10 percent or more for irregular work. Do not enter 0 when the shape has curves, tapers, or hand trimming.Price per ton
Optional supplier price used to estimate material cost before delivery fees and taxes.
Unit: USD per US ton. Enter the quoted material price per US short ton. Leave 0 if you only need quantity.Assumptions and limits
- Larger stones need more depth for full visual coverage.
- Landscape fabric does not reduce rock volume.
- Beds with many curves need waste allowance.
- Does not account for boulders or edging displacement.
- Very large rock may need hand placement.
- Plants and mulch openings can reduce actual coverage.
Research basis: NIST unit conversions. Full methodology and image-credit notes are maintained on the Editorial Policy page.