Mulch Calculator
Measure your beds and choose a depth to see how much mulch you need in cubic yards and bags, for rectangles, circles, triangles and rings around trees. Compare bagged and bulk prices to see which is cheaper.
Mulch calculator
Enter each bed in feet and the mulch depth in inches.
| Shape | Length or diameter | Width (rectangle/triangle) or inner diameter (ring) | Depth (inches) | Volume |
|---|---|---|---|---|
How much mulch do I need?
Square feet × depth in inches ÷ 324 = cubic yards. A 200 sq ft bed at 3 inches needs 200 × 3 ÷ 324 = 1.85 cubic yards, or 25 bags of 2 cu ft (one cubic yard = 13.5 bags of 2 cu ft).
- Depth: 2–3 inches is the usual recommendation for beds; more can hold too much moisture against plants. Keep mulch a few inches away from tree trunks and stems instead of piling it up.
- Bulk vs bags: bulk is usually cheaper per yard for larger jobs, but delivery fees can outweigh the saving on small ones.
- Rings around trees: use the border shape with the outer and inner diameters.
Common questions
How many bags of mulch are in a yard?
13.5 bags of 2 cubic feet, or 18 bags of 1.5 cubic feet.
How much area does a yard of mulch cover?
About 162 sq ft at 2 inches deep, 108 sq ft at 3 inches.
How deep should mulch be?
Usually 2 to 3 inches for garden beds, according to university extension guidance.
How do I calculate mulch for a circle around a tree?
Use the border shape: outer diameter and the trunk-clearance diameter, then the depth.
Is bulk mulch cheaper than bags?
Usually for more than a couple of yards. Compare both, including delivery, with the cost fields above.
Sources
- University of Maryland Extension: Mulching landscape plants
- NIST Handbook 44, Appendix C: volume units
Related
General information, not financial, tax or legal advice. Check important numbers with the official source before acting on them.