Mulch & Soil Calculator
Find how much mulch, topsoil, or gravel a bed needs in cubic yards and cubic feet from the area and depth, plus the number of bags. Calculates in your browser.
Material needed
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Show the math
Volume is the bed area times the depth, converted to yards:
cubic feet = area × (depth ÷ 12)
cubic yards = cubic feet ÷ 27; bags = ⌈cubic feet ÷ bag size⌉
A 2–3 inch mulch layer suppresses weeds without smothering roots. Bulk by the cubic yard is usually cheaper for large beds; bags suit small jobs. All math runs locally in your browser.
What this does
A mulch & soil calculator finds how much mulch, topsoil, or gravel a bed needs in cubic yards and feet from the area and depth, plus the number of bags.
How to use it
- Enter the bed area.
- Enter the depth.
- Enter the bag size.
- Read the cubic yards and bags.
How it works
A 2–3 inch layer suppresses weeds. A cubic yard is 27 cubic feet, about 13.5 bags of a 2 cu ft bag.
cubic yards = area × depth (ft) ÷ 27
Understanding your result
Depth drives the volume, so a 2 to 3 inch layer of mulch is the sweet spot for suppressing weeds and holding moisture without smothering roots. Bulk by the cubic yard is far cheaper than bags once you need more than a bed or two, and keep mulch pulled back from stems and trunks, since piling it against them invites rot and pests.
Example
A 100 sq ft bed 3 inches deep needs about 0.93 cubic yards.
Sources & methodology
Last updated .
Frequently asked questions
How deep should mulch be?
A 2–3 inch layer suppresses weeds and holds moisture without smothering roots; topsoil and gravel beds vary by use.
How many bags are in a cubic yard?
A cubic yard is 27 cubic feet, so it takes about 13.5 bags of a 2 cu ft bag. The tool rounds bags up from your bag size.
Bags or bulk?
Bulk by the cubic yard is usually cheaper for large beds; bags are convenient for small jobs. The tool reports both.
Is anything stored?
No. Everything is calculated locally in your browser.
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