Mulch Calculator
Calculate mulch volume in cubic yards or metres, bag quantity, bulk loads and cost for rectangular garden beds.
Default project preview
2.04 yd³
Bag quantity
28 bags
Base volume
1.85 yd³
Truck equivalent
0.2
Bulk cost
$91.67
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Volume = length × width × depth. Order volume = base volume × extra allowance. Bag count = round up (order volume ÷ volume per bag).
BuildMeter Guides
Understand the measurements and assumptions
Use these visible reference guides before changing project inputs or planning allowances.
FAQ
Mulch Calculator questions
How deep should mulch be?+
Two to four inches is common for many landscape beds. Existing mulch, plant type and drainage can change the ideal depth.
Is bulk mulch cheaper than bags?+
Bulk delivery is often economical for larger projects, but delivery charges and minimum order quantities matter.
Why add extra mulch?+
An allowance helps cover uneven ground, settling and measurement differences.
Project guide
Use this calculator with confidence
Last reviewed: July 19, 2026
Use the mulch calculator to convert planting-bed area and depth into cubic yards, cubic metres or bags. The geometry is straightforward, but actual coverage changes with settling, particle size and the existing surface. Enter the finished depth you want after spreading and compare the rounded bulk or bag quantity with the supplier’s stated package volume.
How to use it
- 1Measure each bed and total the areas.
- 2Subtract large plants, paths or structures only when meaningful.
- 3Enter the desired finished mulch depth.
- 4Choose bulk yards or the exact bag volume sold locally.
Worked example
A 300 ft² bed at 3 in. deep requires 75 ft³, or about 2.78 yd³. With 10% extra for settling and uneven ground, the planning order is about 3.06 yd³.
What the defaults mean
3 in. depth
A familiar example only; use the depth appropriate to the landscape plan.
10% extra
Allows for settling and surface irregularity.
Bag volume
Must match the printed package size.
| Depth | Coverage per cubic yard | Coverage per cubic metre |
|---|---|---|
| 2 in / 50 mm | about 162 ft² | about 20 m² |
| 3 in / 75 mm | about 108 ft² | about 13.3 m² |
| 4 in / 100 mm | about 81 ft² | about 10 m² |
Common measurement mistakes
- Entering square yards as square feet.
- Using loose pile height instead of finished spread depth.
- Forgetting that old mulch may reduce new volume.
- Comparing bulk yards with bags without converting volume.
Limits and safety
- Does not recommend mulch type or horticultural depth.
- Bag volume and bulk delivery practices differ.
- Keep mulch placement appropriate around trunks and structures.
Continue the project
estimate mulch delivery loads and cost — Turn bulk volume into a delivered order.
calculate a tree mulch ring — Use circular geometry around trees.
estimate landscape fabric below beds — Plan rolls and overlap.
calculate bed edging length — Measure the exposed perimeter.