Mulch Volume Calculator Formula

Understand the math behind the mulch volume calculator. Each variable explained with a worked example.

Formulas Used

Cubic Yards

cubic_yards = vol_cuft / 27

Bags Needed

num_bags = bag_size > 0 ? ceil(vol_cuft / bag_size) : 0

Total Volume

volume_cuft = vol_cuft

Variables

VariableDescriptionDefault
area_sqftTotal Bed Area(sq ft)300
depth_inMulch Depth(in)3
bag_sizeBag Size(cu ft)2
vol_cuftDerived value= area_sqft * depth_in / 12calculated

How It Works

Mulch Volume Calculation

Volume = Area x Depth (in feet)

Convert depth from inches to feet by dividing by 12. Divide cubic feet by 27 for cubic yards, or divide by bag size for the number of bags. For bulk delivery, 1 cubic yard covers about 108 sq ft at 3 inches deep.

Worked Example

300 sq ft of beds at 3 inches, using 2 cu ft bags.

area_sqft = 300depth_in = 3bag_size = 2
  1. 01Volume = 300 x (3/12) = 75 cu ft
  2. 02Cubic yards = 75 / 27 = 2.8
  3. 03Bags = 75 / 2 = 38 bags

Ready to run the numbers?

Open Mulch Volume Calculator