Mulch calculator
Enter the size of your beds and the depth of mulch. See cubic yards and bags.
How much mulch you need
Area (sq ft) x depth (in) / 12 gives cubic feet. Divide by 27 for cubic yards. A bed of 100 square feet at 3 inches deep is 25.00 cubic feet, or 0.93 cubic yards. In 2 cubic foot bags that is 13 bags.
| Depth | Square feet per cubic yard | Bags of 2 cu ft per 100 sq ft |
|---|---|---|
| 1 inch | 324 | 5 |
| 2 inches | 162 | 9 |
| 3 inches | 108 | 13 |
| 4 inches | 81 | 17 |
Bags or bulk
Bags are easy to carry and good for small beds. Bulk mulch is sold by the cubic yard and is usually cheaper per cubic foot once you need more than a few yards. Check the size on the bag, since bags come in different volumes.
Tips for spreading
- Two to three inches is common for beds. Thicker layers can hold too much water against plants.
- Keep mulch from piling against trunks and stems.
- Measure odd shapes by splitting them into rectangles and adding the areas. Enter the total in the area box.
For gravel beds and paths, use the gravel calculator.
Questions people ask
How many bags of mulch do I need for 100 square feet?
At 3 inches deep, about 13 bags of 2 cubic foot mulch.
How much does a cubic yard of mulch cover?
About 108 square feet at 3 inches deep, 162 square feet at 2 inches and 324 square feet at 1 inch.
How many 2 cubic foot bags make a cubic yard?
13.5, so buy 14. A cubic yard is 27 cubic feet.
How deep should mulch be?
Two to three inches is a common depth for garden beds.