🌳 Mulch Calculator
Enter the garden bed length and width in feet and the depth in inches.
Mulch needed
How the Mulch Calculator works
Volume is area × depth. Most landscapers recommend about 2–3 inches of mulch. One cubic yard (27 ft³) covers about 108 ft² at 3 inches deep.
Cubic feet = L × W × Depth(in) ÷ 12
Cubic yards = Cubic feet ÷ 27
Bags = Cubic feet ÷ Bag size
Step-by-step calculation
- 1Measure bed length and width.
- 2Choose the depth.
- 3Convert to cubic yards and bags.
Worked example
A 20 × 10 ft bed at 3 inches deep needs 50 ft³ = 1.85 cubic yards, or 25 bags of 2 ft³ (17 bags of 3 ft³).
Mulch Calculator examples
| Length (ft) | Mulch needed |
|---|---|
| 10 | 0.93 cubic yards |
| 15 | 1.39 cubic yards |
| 20 | 1.85 cubic yards |
| 25 | 2.31 cubic yards |
| 30 | 2.78 cubic yards |
Other inputs kept at the calculator's default values. Results calculated by this calculator.
Why use a Mulch Calculator?
Buy the right amount of mulch for garden beds.
Important factors that can affect your results
- Mulch settles over time.
- Existing mulch depth.
- Bag sizes.
Frequently asked questions
How deep should mulch be?
About 2–3 inches. Keep it a few inches away from tree trunks and plant stems.
How much does a cubic yard cover?
About 324 ft² at 1 inch, 162 ft² at 2 inches or 108 ft² at 3 inches.
Related calculators
Last reviewed November 2026 · How we build and check our tools · Report a problem