Mulch Calculator
Mulch is evaluated from Length, Width and Desired Depth. The calculation reports Cubic Feet, Cubic Yards and Bags Needed.
Results
About the Mulch Calculator
The calculator uses a multi formula configuration. Each reported value is read as a direct evaluation of the stored rules with the declared field formats and units.
Formula basis:
Cubic feet = length (ft) x width (ft) x depth (in) / 12
Cubic yards = cubic feet / 27
Bags = cubic feet / bag size (rounded up)
Add 5 - 10% waste factor for uneven areas or settling.
Interpret the outputs in the order shown by the result fields. Optional inputs affect only the outputs that depend on those variables.
Formula & How It Works
The calculation applies the following relations exactly as recorded in the metadata: Cubic feet = length (ft) x width (ft) x depth (in) / 12 Cubic yards = cubic feet / 27 Bags = cubic feet / bag size (rounded up) Add 5 - 10% waste factor for uneven areas or settling. Each output field is produced by substituting the supplied inputs into the relevant relation and then applying the declared rounding or text format.
Worked Examples
Example 1: Front garden bed: 20 ft × 8 ft, 3 inches deep
Inputs
With Length = 20, Width = 8, Desired Depth = 3 and Bag Size = 2 cubic feet (standard small bag) as the stated inputs, the result is Cubic Feet = 40 ft^3, Cubic Yards = 1.48 yd^3 and Bags Needed = 20 bags. Each value corresponds to the declared output fields.
Example 2: Large backyard beds: 50 ft × 12 ft, 4 inches deep
Inputs
With Length = 50, Width = 12, Desired Depth = 4 and Bag Size = 3 cubic feet (large bag - most common) as the stated inputs, the result is Cubic Feet = 200 ft^3, Cubic Yards = 7.41 yd^3 and Bags Needed = 67 bags. Each value corresponds to the declared output fields.
Example 3: Tree ring: 10 ft diameter, 3 inches deep
Inputs
With Length = 10, Width = 10, Desired Depth = 3 and Bag Size = 2 cubic feet (standard small bag) as the stated inputs, the result is Cubic Feet = 25 ft^3, Cubic Yards = 0.93 yd^3 and Bags Needed = 13 bags. Each value corresponds to the declared output fields.
Example 4: Vegetable garden path: 40 ft × 2 ft, 2 inches
Inputs
With Length = 40, Width = 2, Desired Depth = 2 and Bag Size = 2 cubic feet (standard small bag) as the stated inputs, the result is Cubic Feet = 13.3 ft^3, Cubic Yards = 0.49 yd^3 and Bags Needed = 7 bags. Each value corresponds to the declared output fields.
Common Use Cases
- Calculate mulch for a rectangular garden bed
- Determine mulch for circular tree rings
- Estimate number of mulch bags to buy from a garden store