Mulch Calculator
Figure out how much mulch or other landscaping material you need. Choose the shape of your mulch bed then enter dimensions. You can use feet, inches, meters or centimeters.
About Mulch and Application Guidelines
What is Mulch and Why Use It?
Mulch is a protective layer of material spread on top of soil, usually around plants. It can be made of wood chips, shredded leaves, straw, grass clippings, stones or rubber. Using the right mulch can help your yard, landscape project or garden, depending on the type of mulch you choose.
Recommended Mulch Depth by Area
| Area | Depth | Notes |
|---|---|---|
| Flower/shrub beds | 2–3 in | Keep mulch a few inches from stems |
| Vegetable beds | 2–3 in | Use clean, weed-free mulch |
| Around trees | 2–3 in | Form a wide ring; keep 3-6 in away from trunk |
| Paths | 3–4 in | Use chunky mulch so it stays put |
| Slopes | 3–4 in | Choose fibrous/chunky mulch to resist wash-off |
| Containers | 1–2 in | Mulch helps soil hold water and stop splashes |
Mulch Volume Formulas and Area Calculations

Calculate mulch volume using depth for a square
Using measurements in feet:
- Area ft2 = 2 × Side Length
- Volume ft3 = Depth × Area
- Volume in Cubic Yards yd3 = Volume ft3 ÷ 27

Calculate mulch volume using depth for a rectangle
Using measurements in feet:
- Area ft2 = Length × Width
- Volume ft3 = Depth × Area
- Volume in Cubic Yards yd3 = Volume ft3 ÷ 27

Calculate mulch volume using depth for a rectangle border
Using measurements in feet:
- Inner Area (ft2) = Length × Width
- Total Area (ft2) = [ Length + (2 × Border Width) ] × [ Width + (2 × Border Width) ]
- Area (ft2) = Total Area − Inner Area
- Volume (ft3) = Depth × Area
- Volume in Cubic Yards (yd3) = Volume (ft3) ÷ 27

Calculate mulch volume using depth for a circle
Using measurements in feet:
- Area (ft2) = Pi × (Diameter ÷ 2)2
- Volume (ft3) = Depth × Area
- Volume in Cubic Yards (yd3) = Volume (ft3) ÷ 27
- Pi = 3.14

Calculate mulch volume using depth for a circle border
Using measurements in feet:
- Outer Diameter = Inner Diameter + (2 × Border Width)
- Outer Area (ft2)
= Pi × (Outer Diameter/2)2 - Inner Area (ft2)
= Pi × (Inner Diameter/2)2 - Area (ft2) = Outer Area − Inner Area
- Volume (ft3) = Depth × Area
- Volume in Cubic Yards (yd3) = Volume (ft3) ÷ 27
- Pi = 3.14
The Circle Border and Annulus below are the same shape, just measured differently.

Calculate mulch volume using depth for an annulus
Using measurements in feet:
- Outer Area (ft2)
= Pi × (Outer Diameter ÷ 2)2 - Inner Area (ft2)
= Pi × (Inner Diameter ÷ 2)2 - Area (ft2) = Outer Area − Inner Area
- Volume (ft3) = Depth × Area
- Volume in Cubic Yards (yd3) = Volume (ft3) ÷ 27
- Pi = 3.14
The Circle Border and Annulus above are the same, just measured differently.

Calculate mulch volume using depth for a triangle
Using measurements in feet:
Area (ft2) = 1/2 × Base × Height
Or, if you don’t have the height of the triangle, but you have the lengths of each triangle side (sides a, b and c), use the below formula for triangle area.
Area = √ { [ (a + b + c) ÷ 2) ] × [ (a + b + c) ÷ 2) − a ] × [ (a + b + c) ÷ 2) − b ] × [ (a + b + c) ÷ 2) − c ] }
Volume (ft3) = Depth × Area
Volume in Cubic Yards (yd3) = Volume (ft3) ÷ 27

Calculate mulch volume using depth for a trapezoid
Using measurements in feet:
- Area (ft2) = [(a + b) ÷ 2 ] × h
- Volume (ft3) = Depth × Area
- Volume in Cubic Yards (yd3) = Volume (ft3) ÷ 27