Rectangular bed
Area = length × width. Volume in cubic feet = area × depth in inches ÷ 12.
Mulch calculator / Mulch coverage chart
Quantity reference
Mulch Coverage Chart
Use this chart to translate a measured area and mulch depth into volume. The example is for 100 square feet, which is the same area as a 10 × 10 ft bed. Bag counts use 2-cubic-foot bags and are rounded up; change the bag size or calculate your exact areas with the mulch coverage calculator.
Planning note: Actual coverage varies with settling, product texture, and how evenly the mulch is spread. Treat the chart as a quantity reference, not a supplier quote.
Depth context: UMN Extension describes 2–4 inches as a general garden mulch range. Choose the depth that fits your plants and site; the table below is a reference, not a universal prescription. Read the UMN Extension guidance.
100 square feet
How much mulch do I need by depth?
| Depth | Cubic feet | Cubic yards | 2 ft³ bags |
|---|---|---|---|
| 1 inch | 8.33 ft³ | 0.309 yd³ | 5 bags |
| 2 inches | 16.67 ft³ | 0.617 yd³ | 9 bags |
| 3 inches | 25.00 ft³ | 0.926 yd³ | 13 bags |
| 4 inches | 33.33 ft³ | 1.235 yd³ | 17 bags |
| 6 inches | 50.00 ft³ | 1.852 yd³ | 25 bags |
The cubic-yard values are cubic feet ÷ 27. Bag counts are cubic feet ÷ 2, rounded up to a whole bag.
Use your own measurements
Mulch coverage formulas
Round bed
Area = π × (diameter ÷ 2)². Then multiply by depth in inches ÷ 12 to get cubic feet.
Bulk quantity
Cubic yards = cubic feet ÷ 27. Confirm how the supplier rounds partial yards and whether an extra allowance is appropriate.
Bag quantity
Bags = cubic feet ÷ the bag's printed cubic-foot volume, rounded up after each area or project total is calculated.
Worked example
A 10 × 10 ft bed at 3 inches
The bed has 100 square feet. Multiplying by 3 inches and dividing by 12 gives 25 cubic feet. Dividing by 27 gives about 0.926 cubic yards. With 2-cubic-foot bags, 25 ÷ 2 = 12.5, so the chart rounds up to 13 bags.
For several beds with different shapes or depths, keep each area separate in the mulch project planner or mulch installation cost calculator.
Common questions
Mulch coverage chart FAQ
Are these bag counts for every bag size?
No. The table uses 2-cubic-foot bags. If your bag is 1.5 or 3 cubic feet, divide the calculated cubic feet by the size printed on that bag and round up.
Should I add extra mulch?
Settling and site conditions can change the order quantity. If you add an allowance, keep the measured volume visible and confirm the final amount with your supplier.
Can I use the chart for a circular bed?
The chart is based on 100 square feet, regardless of shape. For a circle, calculate its area from the diameter first, then use the same depth and volume formulas.
Related mulch tools
Calculate, price, and plan the job
Mulch coverage calculator
Calculate quantities for rectangles, circles, multiple areas, and mixed units.
Installation cost calculator
Enter local material, delivery, and labor rates for a per-area estimate.
Project planner
Turn measured areas into an order quantity and installation checklist.
Bags per cubic yard chart
Convert a bulk cubic-yard quantity into whole bags by the package size.
How much mulch do I need?
Follow the formulas with rectangle and circle examples.