Mulch Calculator works out how much mulch a bed needs, in cubic feet and cubic yards, plus how many bags to buy. Enter the bed's area and the depth you want to spread — a common depth is 2 to 3 inches — in US units (square feet and inches) or metric (square meters and centimeters), and the tool converts everything internally. It divides the volume by the bag size you specify (bagged mulch is commonly sold in 2 cubic foot bags) and rounds up so you know exactly how many bags to load into the cart. It is built for gardeners refreshing flower beds, landscapers quoting a job, and homeowners planning a weekend mulching project who want a quick, reliable number before heading to the store. Every calculation runs locally in your browser.
Features
Converts bed area and depth into cubic feet and cubic yards in one step
Switch between US units (square feet/inches) and metric (square meters/centimeters)
Custom bag size field so bag counts match whatever size you actually buy
Bag counts round up so you never come up short at the register
Results shown in cubic yards, cubic meters and cubic feet side by side
One-click copy of a plain-text summary of every result
Clear error message when area or depth is missing or zero
Runs entirely in your browser — no project details are uploaded
How to use the Mulch Calculator
Choose US or Metric units
Enter the bed's area and how deep you want the mulch layer
Set the bag size you plan to buy (default 2 cubic feet)
Read the cubic yards and bag count, then copy the summary
Example
Input
200 sqft, 3 in deep
Output
1.85 cu yd (25 bags)
200 sq ft x 3 in / 12 = 50 cu ft, or 1.85 cu yd; 50 / 2 cu ft per bag rounds up to 25 bags.
Common errors & troubleshooting
Depth entered as a whole foot instead of inches, giving a wildly oversized volume. — In US mode, depth is inches, not feet — a typical mulch layer is 2 to 4 inches deep, not 2 to 4 feet.
Bag count seems too high compared to what the bag label suggests. — Check the bag size field matches your actual bags — 2 cubic foot bags are common, but some brands sell 1 or 3 cubic foot bags.
Bought exactly the calculated number of bags and ran short. — The Mulch Calculator gives a baseline estimate — irregular beds and settling can use more mulch than a flat rectangle assumption, so add a small buffer before ordering.
Bulk mulch delivery quote is in cubic yards but the bed was measured in square feet. — Switch to the cubic yards result — the calculator already converts your area and depth into cubic yards for bulk orders.
Frequently asked questions
How does the Mulch Calculator estimate cubic yards?
It multiplies bed area by depth, converts inches to feet, then divides the cubic feet by 27 to get cubic yards — the standard unit bulk mulch is sold in.
How deep should I spread mulch, according to the Mulch Calculator?
Most garden beds use 2 to 3 inches of mulch; deeper layers (4 inches or more) can smother roots, so the calculator lets you test different depths before ordering.
Does the Mulch Calculator work for both bagged and bulk mulch?
Yes. It shows cubic yards for bulk delivery orders and a bag count based on whatever bag size (cubic feet) you enter for bagged mulch.
Can I use the Mulch Calculator with metric measurements?
Yes. Switch to Metric to enter bed area in square meters and depth in centimeters — the calculator converts internally and still shows cubic yards and cubic meters.
Is my bed size and project data uploaded when I use the Mulch Calculator?
No. All areas, depths and results stay in your browser and are never uploaded to ArrayKit.
Why does the Mulch Calculator round the bag count up?
Bag counts always round up to the next whole bag so the total covers the full volume needed — buying a partial bag isn't possible, and rounding down would leave you short.
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