Mulch Calculator
Calculate mulch volume in cubic yards and bags for any bed size and depth.
About Mulch Calculator
Mulch volume in cubic yards equals (area in sq ft × depth in inches) ÷ 324. The constant 324 comes from 27 cubic feet per cubic yard × 12 inches per foot. Bags are rounded up to ensure you have enough. Recommended mulch depth is 2–4 inches; less won't suppress weeds, more can rot plant crowns.
Formula
Volume
Cubic yards = (area sq ft × depth inches) ÷ 324
- A_{sq\,ft}
- Area in sq ft
- d_{in}
- Depth in inches
Worked example
With the default values below, Mulch Calculator returns Cubic Yards of 0.926. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Bed Lengthminimum 0.1 ft
- 20 ft
- Bed Widthminimum 0.1 ft
- 5 ft
- Mulch Depthaccepts 0.5–24 in
- 3 in
- Bag Sizeone of 1.5 cu ft bag, 2 cu ft bag (most common), 3 cu ft bag
- 2 cu ft bag (most common)
- Number of Bedsminimum 1
- 1
- Price per Bag (optional)minimum 0 $
- 0 $
Results
- Cubic Yards
- 0.926
- Bags Needed
- 13
- Cubic Feet
- 25.00
- Total Area
- 100.0 sq ft
Step by step
- 1Area= 100 sq ft
- 2Cubic yards= 0.926 yd³
- 3Convert to cubic feet= 25.00 cu ft
- 4Bags needed (2 cu ft bags)= 13 bags
Assumptions and limits
- The result is derived only from the 6 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax or compounding frequency into account.
- Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How deep should I apply mulch?
2–3 inches for most garden beds. 3–4 inches for weed suppression and moisture retention. Never more than 4 inches around tree bases — 'mulch volcanos' cause root rot and bark decay.
How many cubic yards does a pickup truck hold?
A standard full-size pickup can hold about 1–2 cubic yards of mulch. A full-size pickup with a high-side extension can hold up to 3 cubic yards. Check the truck's payload rating before loading.
Why is the calculation ÷ 324?
There are 27 cubic feet in a cubic yard. To convert sq ft × inches to cubic feet you divide by 12; to then convert to cubic yards you divide by 27. Combined: ÷ 12 ÷ 27 = ÷ 324.
When should I buy bags vs. bulk?
Bulk delivery (by the cubic yard) is usually more economical above 3 cubic yards. Below that, bagged mulch avoids delivery fees and is easier to handle.