Mulch Cubic Yards Calculator
Mulch is bought either in bulk by the cubic yard or in bags measured in cubic feet, so the first step is always volume. Multiply the bed length by its width and by the depth in feet to get cubic feet, then divide by 27 to convert to cubic yards. Divide the cubic feet by your bag size to get bag count. This calculator does all three so you can compare bulk and bagged ordering for the same bed and depth, using nothing but exact geometric conversions.
Mulch volume formula
Depth in feet = depth inches / 12
Cubic feet = length * width * depth in feet
Cubic yards = cubic feet / 27
Bags needed = ceil(cubic feet / bag size)
Bed area = length * width
One cubic yard equals 27 cubic feet, so dividing cubic feet by 27 gives cubic yards. Bagged mulch is sold in cubic feet, so dividing total cubic feet by the bag size and rounding up gives the number of bags.
Mulch ordering notes
- One cubic yard equals 27 cubic feet; this is the conversion used for all bulk landscaping material.
- A typical mulch depth is 2 to 4 inches; depth in inches is divided by 12 to convert to feet.
- Bagged mulch is most commonly sold in 2 cubic foot bags, so a cubic yard is about 13.5 bags.
- Mulch is laid loose and not compacted, so the bought volume closely matches the spread volume.
- For irregular beds, split into rectangles, add the areas, then enter the total footprint as length times width.
Mulch: frequently asked questions
How many cubic yards of mulch do I need?
Multiply the bed length by the width and by the depth in feet to get cubic feet, then divide by 27 to get cubic yards, because one cubic yard equals 27 cubic feet. For example, a 200 square foot bed at 3 inches deep is 200 times 0.25, which is 50 cubic feet, or about 1.85 cubic yards.
How deep should mulch be?
A common landscaping depth is 2 to 4 inches. Shallower than 2 inches lets weeds through and dries quickly; deeper than 4 inches can suffocate roots and waste material. Enter your chosen depth in inches and the calculator converts it to feet before computing volume.
How many bags of mulch are in a cubic yard?
Bagged mulch is sold in cubic feet, most often 2 cubic foot bags. Since a cubic yard is 27 cubic feet, one cubic yard equals about 13.5 of the 2 cubic foot bags. This calculator divides your total cubic feet by the bag size you enter and rounds up to whole bags.
Should I order bulk or bagged mulch?
Bulk mulch delivered by the cubic yard is usually cheaper per unit volume for large beds, while bags are convenient for small jobs and easy to carry. The break-even depends on local pricing. This calculator gives both the cubic yards for bulk ordering and the number of bags for bagged purchase.
Does mulch settle or compress?
Fresh mulch settles modestly as it weathers, but unlike soil or gravel it is laid loose and not compacted, so the volume you spread is close to the volume you buy. Order a small surplus for topping up thin spots rather than a large compaction allowance.
Official sources
- U.S. National Institute of Standards and Technology: Unit conversion (cubic yard, cubic foot).
- U.S. Department of Agriculture Forest Service: Mulching guidance for landscapes.
Reviewed by the CalculatorHub team, edited by James Graham, 16 June 2026. See our methodology.