Mulch Calculator
Mulch conserves moisture and finishes beds. This tool estimates volume from bed size and layer thickness.
Step 2
Enter project measurements
Use decimals if needed (e.g. 3.5).
Step 3
How to use this calculator
Measure the coverage rectangle and average depth you want after compaction. Deeper sections can be averaged or split into multiple runs.
What the math is doing
Volume is length × width × depth. Weight multiplies volume by a typical bulk density for that material.
How to measure
Stake the area and run a string line for straight edges. Depth is from existing grade to finished grade.
Frequently asked questions
How deep should mulch be?
2–3 in is common for shredded bark; too deep can suffocate roots.
Bags vs bulk?
Convert final cubic feet to bag size from the retailer label.
Dyed mulch coverage?
Volume is the same; settle allowance is still handled with waste percent.
Rock vs organic mulch?
Rock densities differ; use gravel tools for stone groundcover.