Mulch Calculator
Find out how much mulch to buy for your garden beds. Enter the bed dimensions and your preferred depth, and get the volume in cubic yards plus the exact number of 2 cu ft and 3 cu ft bags.
You need approximately
| Bag size | Bags needed |
|---|---|
| 2 cu ft bag (standard) | |
| 3 cu ft bag (large) |
How this mulch calculator works
Volume = bed area × depth. The result is converted to cubic yards (1 cubic yard = 27 cubic feet). Bag counts divide the volume by the standard retail bag sizes of 2 and 3 cubic feet and round up to whole bags.
For quick reference coverage numbers at different depths, see the mulch coverage chart. For irregular beds, split the area into rectangles, calculate each, and add the results together.
Frequently asked questions
How much does a yard of mulch cover?
One cubic yard of mulch covers about 108 square feet at a 3-inch depth, 162 square feet at 2 inches, and 324 square feet at 1 inch. Divide 27 cubic feet by the depth in feet to get the coverage.
How many bags of mulch equal a cubic yard?
A cubic yard is 27 cubic feet, so it equals 13.5 standard 2-cubic-foot bags or 9 large 3-cubic-foot bags. Buying in bulk by the yard is usually cheaper once you need more than 10–15 bags.
How deep should mulch be?
A 2–3 inch layer is recommended for most beds: enough to suppress weeds and retain moisture without suffocating roots. Keep mulch a few inches away from trunks and stems.
Should I buy mulch in bags or in bulk?
Bags are convenient for small beds and are easy to transport in a car. For anything above roughly one cubic yard, bulk delivery by the yard typically costs significantly less per cubic foot.
Formulas last reviewed on 2026-07-02. This tool provides planning estimates only. Actual coverage varies with mulch type, moisture, and how evenly it is spread.