Calculator 04 / 08
Landscape rock calculator
Beds and borders are rarely one rectangle. Add each part of the bed — rectangles, circles, triangles or a known area — and get one total.
- Outputs
- yd³ · tons · tonnes · bags · cost
- Material basis
- Landscape rock · 105 lb/ft³ default, editable
- Method
- Formulas & sources
Measuring a bed that isn't a rectangle
Curved or angled beds are easier to measure in pieces: a rectangle for the straight run, a triangle for an angled corner, a circle around a tree. Where pieces overlap, trim one so the overlap isn't counted twice. If you already know the area from a plan, use Known area.
Worked example: border plus tree ring
| Border | 20 ft × 3 ft = 60 ft² |
|---|---|
| Tree ring | 6 ft diameter = 28.27 ft² |
| Total at 3 in | 88.27 ft² × 0.25 ft = 22.07 ft³ = 0.82 yd³ |
| + Waste 10% | 24.28 ft³ = 0.90 yd³ ≈ 1.27 US tons at 105 lb/ft³ |
Landscape rock vs. gravel
“Landscape rock” covers everything from 3/4 in decorative gravel to fist-size stone. Larger pieces need a deeper layer to cover the ground, and the air between them changes the weight per yard. We don't have a reliable published density for decorative rock, so the default is the general dry-gravel value source — replace it with the supplier's number when you pick a product. For rounded stone in drainage channels, use the river rock calculator.
Questions
How much landscape rock do I need?
Measure each part of the bed, choose a depth that covers the soil for the rock size you're using, and add the areas here. The result gives cubic yards to order in bulk, tons if the supplier sells by weight, and bags for small areas.
How deep should landscape rock be?
Deep enough to cover the ground with the size of rock you've chosen: small gravel can be thinner, larger stone needs more depth. Try a few depths — the calculator shows how much each one changes the order.
Is weed fabric included?
No. The calculator estimates rock only. Fabric, edging and delivery are separate items.