Mulch for 400 square feet, by depth
| Depth | Cubic yards | Cubic feet | 2 ft³ bags | 3 ft³ bags |
|---|---|---|---|---|
| 2 in | 2.47 | 66.7 | 34 | 23 |
| 3 in | 3.70 | 100.0 | 50 | 34 |
| 4 in | 4.94 | 133.3 | 67 | 45 |
What 400 square feet looks like
- A square about 20.0 × 20.0 ft.
- A 4 ft wide border that is 100 ft long, or a 3 ft wide border 133 ft long.
- A round bed about 22.6 ft across.
Bulk or bags for 400 ft²?
At 3.70 cubic yards, bulk is almost certainly the better choice. 50 bags would be heavy work and cost far more per cubic foot. Ask your supplier about delivery, and where the truck can tip the pile.
Want to change anything else? The calculator above is the full Mulch Calculator: edit any number and the results update instantly.
Tools & materials for this project
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Frequently asked questions
How many bags of mulch for 400 square feet?
At the usual 3 inch depth you need 50 bags of 2 ft³ (or 34 bags of 3 ft³). At 2 inches it is 34 bags of 2 ft³, and at 4 inches 67 bags.
How many cubic yards of mulch for 400 square feet?
3.70 cubic yards at 3 inches deep, 2.47 at 2 inches and 4.94 at 4 inches. Round up to the next quarter yard when you order.
How deep should I spread mulch over 400 square feet?
Two to three inches is right for most beds. Keep it a few inches back from tree trunks and stems, and top up with an inch or so each year.
Related sizes and guides
Estimates only. Results assume standard materials and simple shapes. Supplier products vary, and the final call on quantity, structure and safety is yours. Check your local code and your supplier's guidance before ordering.