Mulch Calculator
Enter your bed dimensions and the mulch depth (2–3 inches is typical). Get the volume in cubic yards plus the number of standard 2 cubic-foot bags.
Updated · How we calculate
Your measurements
Bagged mulch is usually 2 ft³; some hardwood and rubber mulch is 1.5 or 3 ft³.
Mulch needed
20 bags
2 ft³ bags · or 1.48 yd³ bulk
Estimates only. Verify against your supplier's coverage figures before ordering.
Footprint
Footprint to scale
Coverage
- Bed area
- 160 ft²
How much mulch for common bed sizes
| Job | Size | Mulch needed | Also |
|---|---|---|---|
| Small flower bed | 10 × 4 ft, 3 in deep | 5 bags | 2 ft³ bags · or 0.37 yd³ bulk |
| Foundation bed | 40 × 4 ft, 3 in deep | 20 bags | 2 ft³ bags · or 1.48 yd³ bulk |
| 500 ft² of beds | 25 × 20 ft, 3 in deep | 63 bags | 2 ft³ bags · or 4.63 yd³ bulk |
| 1,000 ft² of beds | 40 × 25 ft, 3 in deep | 125 bags | 2 ft³ bags · or 9.26 yd³ bulk |
| Refresh layer, 500 ft² | 25 × 20 ft, 1 in deep | 21 bags | 2 ft³ bags · or 1.54 yd³ bulk |
| Play area | 30 × 20 ft, 6 in deep | 150 bags | 2 ft³ bags · or 11.11 yd³ bulk |
Figures use this calculator's default settings; tap one above the inputs to load it and adjust.
The formula
Bags = (Length ft × Width ft × (Depth in ÷ 12)) ÷ bag size (ft³)
Example: A 20 ft × 8 ft bed at 3 in deep = 40 ft³ → 20 × 2 ft³ bags, or 1.48 yd³ bulk.
How it works
- 1Multiply bed area by depth (in feet) to get cubic feet.
- 2Bagged mulch is usually sold in 2 ft³ bags — divide cubic feet by the bag size.
- 3Bulk mulch is sold by the cubic yard (27 ft³) and is cheaper for large beds.
Frequently asked questions
How deep should mulch be?
2–3 inches is ideal. Deeper than 3 inches can suffocate roots and waste material; thinner won't suppress weeds well.
How many bags of mulch are in a cubic yard?
A cubic yard is 27 cubic feet, so it takes 13.5 of the common 2 ft³ bags (buy 14), 9 of the 3 ft³ bags, or 18 of the 1.5 ft³ bags.
How much area does a cubic yard of mulch cover?
One cubic yard covers 324 ft² at 1 inch deep, 162 ft² at 2 inches, 108 ft² at 3 inches and 81 ft² at 4 inches.
How much area does one bag of mulch cover?
A 2 ft³ bag covers 12 ft² at 2 inches deep, 8 ft² at 3 inches and 6 ft² at 4 inches.