Calculate how much mulch, gravel, topsoil, sand, or compost you need for any landscape project. Get results in cubic yards, tons, and bag counts for both 2 and 3 cubic foot bags. Supports rectangle, circle, triangle, and custom area shapes.
Recommended depths for common uses.
| Use | Depth | Note |
|---|---|---|
| Flower beds (mulch) | 2–3" | Retains moisture, suppresses weeds |
| Walkways (gravel) | 3–4" | Stable footing, good drainage |
| Garden beds (topsoil) | 4–6" | Amend or build raised beds |
| Paver base (sand) | 1–2" | Leveling layer under pavers |
| Lawn topdressing | ¼–½" | Thin layer for overseeding |
Mulching a 20×30 foot garden bed at 3 inches deep? You need approximately 5.6 cubic yards of mulch — that's about 75 bags of 2-cubic-foot mulch or 50 bags of 3-cubic-foot mulch. At roughly 800 pounds per cubic yard, that's about 2.2 tons. For jobs over 5 cubic yards, bulk delivery ($30–$45 per yard) is significantly cheaper than buying bags ($4–$6 each).
| Depth | Area Covered per Cubic Yard |
|---|---|
| 1 inch | 324 sq ft |
| 2 inches | 162 sq ft |
| 3 inches | 108 sq ft |
| 4 inches | 81 sq ft |
| 6 inches | 54 sq ft |
2–3 inches for garden beds and around trees. 3–4 inches for weed suppression. Never mulch deeper than 4 inches around plants as it can suffocate roots and trap moisture.
Approximately 400–800 pounds depending on moisture content and material type. Freshly chipped wet mulch is heavier than dry aged mulch.
Bulk is almost always cheaper for jobs over 3 cubic yards. Bulk mulch runs $30–$50 per yard delivered versus $4–$6 per 2-cubic-foot bag (equivalent to roughly $55–$80 per yard).
A typical single-car driveway (10×40 ft at 4 inches deep) needs about 5 cubic yards of gravel, weighing roughly 6.7 tons. A two-car driveway (16×40 ft) needs about 8 cubic yards.
Organic mulch breaks down over 1–2 years. Top up annually with 1–2 inches of fresh mulch. Gravel and rock are permanent and only need occasional raking.
Not sure whether to use mulch or rock? See our mulch vs rock comparison.
Typical Results
💡 Refreshing existing mulch? You usually only need 1–2" on top, not a full 3".