Landscape material calculator · mulch v1.0
Mulch Calculator
Calculate mulch for a bed, border or irregular landscape area. See geometric volume, an editable ordering allowance, supplier-rounded bulk yards, whole bags and optional cost without hiding how one becomes the next.
✓No signup
✓Bulk + bags
✓Editable allowance
✓Irregular areas
Step 1
Project details
Measure the area, check the project preview and enter the new mulch depth you actually need. If mulch is already present, measure it before deciding how much additional depth to enter.
Project measurement
Ordering & pricing
Advanced assumptions
How to calculate how much mulch you need
Measure the area that will receive mulch, multiply it by the new mulch depth, then convert the volume to cubic yards or cubic feet. JobsiteMeasure shows the exact volume first, applies only the allowance you choose, then rounds bulk mulch to the selected supplier increment or bags to a whole package.
Area (ft²) × depth (in) ÷ 12 = mulch volume (ft³)
Mulch volume (ft³) ÷ 27 = cubic yards
Adjusted volume (ft³) ÷ labelled bag volume (ft³) = bags, rounded up
Mulch coverage by depth
One cubic yard contains exactly 27 cubic feet. The coverage below is pure geometry before an ordering allowance or supplier rounding:
| New mulch depth | Coverage from 1 yd³ |
|---|---|
| 1 in | 324 ft² |
| 2 in | 162 ft² |
| 3 in | 108 ft² |
| 4 in | 81 ft² |
These are volume conversions, not instructions to apply that depth. Measure any existing mulch and use only the additional depth required for the project.
Bulk mulch vs bags
Bulk mulch is normally quoted by cubic yard. Bagged mulch is labelled in cubic feet, and package sizes vary. One cubic yard is 27 ft³, so it is equivalent by labelled volume to 18 × 1.5 ft³ bags, 13.5 × 2 ft³ bags or 9 × 3 ft³ bags before allowance. Actual purchasing rounds upward to whole bags.
Enter your supplier's bulk increment, the volume printed on the bag and any prices above. Delivery is included only in the bulk-cost comparison when you enter a delivery fee.
Choosing the mulch depth to enter
Depth depends on the material, the plants, the purpose of the mulch and how much is already present. The calculator starts at 3 inches because that is a source-supported landscape context, but it remains editable. The University of Minnesota Extension recommends a 3-inch organic-mulch layer around newly planted trees and shrubs, says not to exceed that layer in that context, and advises keeping mulch away from the trunk.
That guidance is not a universal specification for every bed or mulch product. Use project- and plant-specific guidance where it is available.
Mulch calculator example
A 20 ft × 10 ft bed at 3 in deep has a geometric volume of 50 ft³, or about 1.85 yd³. With a 10% allowance the adjusted requirement is about 2.04 yd³. A supplier selling in 0.5 yd³ increments produces a practical order of 2.5 yd³. If the selected bags contain 2 ft³, the adjusted requirement is 55 ft³ and rounds up to 28 bags.
Mulch calculator FAQs
How many bags of mulch do I need?
The calculator divides the adjusted cubic-foot requirement by the labelled volume of the bag you select and rounds upward to a whole bag. Check the exact package because mulch bag sizes vary.
How many cubic feet are in a yard of mulch?
One cubic yard contains exactly 27 cubic feet. A bulk yard therefore covers 108 ft² at 3 inches deep before any allowance.
Can I calculate an irregular landscape bed?
Yes. Use Irregular / multi-section mode to add rectangles, triangles, circles, semicircles and trapezoids, and subtract islands or other cut-outs.
Should I include mulch that is already in the bed?
Measure the existing layer and enter only the new depth you plan to add. Automatically adding a full starting depth on top of existing mulch can overstate the quantity and create an excessive layer.
Why is the recommended bulk order higher than the exact volume?
The calculator keeps three stages separate: geometric volume, the allowance you selected and upward rounding to the supplier increment. The detailed result shows each stage.