Mulch Calculator

Find how many cubic yards or bags of mulch to cover your garden beds at the depth you want, and what it will cost.

Shape
Most beds need 2″ to 3″ of mulch; up to 4″ for weed control.
Material
Dry wood mulch weighs roughly 400 to 700 lb per cubic yard; wet mulch 800 to 1,000.
%
A little extra covers edges and uneven beds.
Bag Size
Cost
$
Fractions work too: try 12 1/2.
Cubic Yards
Area
Cubic feet
Cubic meters
Weight
Bags
Cost
Add a price to estimate

Garden Beds

Areas you add are saved in this browser.

AreaSizeDepthCubic YardsTonsCostRemove

How to Calculate Mulch

Multiply the bed's length and width in feet by the depth in inches ÷ 12 to get cubic feet. Divide by 27 for cubic yards if you're buying bulk, or by the bag size (usually 2 or 3 cubic feet) to get the number of bags.

Cubic yards = length (ft) × width (ft) × depth (in) ÷ 12 ÷ 27
Tons = cubic yards × weight per cubic yard (lb) ÷ 2,000

There are 27 cubic feet in a cubic yard (3 × 3 × 3). For a circle, the area is 3.1416 × diameter² ÷ 4; for a triangle, base × height ÷ 2.

Worked Example

Mulch Weights

NameLb. per Cubic YardTons per Cubic YardNotes
Wood or bark mulch, dry5500.28Shredded hardwood, bark or chips
Wood mulch, wet9000.45Freshly delivered or rained on
Rubber mulch1,1000.55Recycled rubber nuggets; check with supplier

How Far a Cubic Yard Goes

DepthOne Cubic Yard CoversNeeded per 100 Sq. Ft.

Tips for Mulching

Keep mulch 2″ to 3″ deep and pull it back a few inches from tree trunks and plant stems to prevent rot. Refresh with about an inch each year rather than piling on more.

One cubic yard is 27 cubic feet, or about 13½ bags of 2 cubic feet. Bulk mulch is usually cheaper once you need more than a couple of yards.