Landscaping calculator
Mulch Calculator for Bags and Yards
Estimate how much mulch to buy for garden beds, tree rings, and landscape borders. Get cubic yards, bag count, coverage, and a quick cost estimate.
How to use the mulch calculator
Enter the bed size, choose your mulch depth, and add a small extra percentage for settling and uneven spreading. The calculator converts the volume into cubic yards and common bag counts so you can compare bagged mulch with bulk delivery.
If your bed is curved or irregular, split it into a few rectangles, add the square feet together, then use the total square feet option.
Common mulch estimates
- 100 sq ft at 2 inches deep: about 0.62 cubic yards before extra allowance.
- 250 sq ft at 3 inches deep: about 2.31 cubic yards before extra allowance.
- One 2 cu ft bag: covers about 12 sq ft at 2 inches deep, or 8 sq ft at 3 inches deep.
FAQ
What formula does this calculator use?
Mulch cubic yards = square feet × depth in inches ÷ 324. The calculator then adds your extra percentage and converts cubic yards into cubic feet and bag counts.
Is bagged mulch or bulk mulch better?
Bagged mulch is convenient for small beds and touch-ups. Bulk mulch is often cheaper for larger projects, especially when you need several cubic yards and have a place for delivery.
Should I remove old mulch first?
If the old layer is matted, moldy, or already too thick, rake it loose or remove some before adding new mulch. If it has mostly broken down, you can usually top it up to the target depth.