How to calculate your mulch project
Mulch coverage depends on bed area and finished depth. Calculate bulk yards and whole bags together, then compare your local prices before buying.
Need the surface area? Measure your outdoor project on our satellite map →
- Measure the bed at its widest practical dimensions.
- Select rectangle, circle, or enter a known combined area.
- Enter the intended depth, bag size, local prices, and a settling allowance.
Formula
The calculation
Area × depth = cubic feet. Divide by 27 for cubic yards or by the selected bag size for whole bags; each quantity is multiplied by its local price for comparison.
Worked example
A 12 × 8 ft bed at 3 inches deep with 10% extra requires about 0.98 cubic yards, or approximately 14 two-cubic-foot bags.
The result is a planning estimate. Round purchasing quantities up to available package sizes and confirm the exact product specifications.
How much area does a cubic yard of mulch cover?
Coverage changes directly with the installed depth. One cubic yard contains 27 cubic feet and covers approximately the following areas before any settling or extra-material allowance.
| Mulch depth | Approximate coverage |
|---|---|
| 1 inch | 324 ft² |
| 2 inches | 162 ft² |
| 3 inches | 108 ft² |
| 4 inches | 81 ft² |
Mulch quantities for common project sizes
These quick-reference quantities use a 3-inch finished depth and do not include extra material for settling or uneven grade. The bag count assumes 2-cubic-foot bags and is rounded up to a whole bag.
| Bed area | Bulk mulch | 2 ft³ bags |
|---|---|---|
| 100 ft² | 0.93 yd³ | 13 bags |
| 250 ft² | 2.31 yd³ | 32 bags |
| 500 ft² | 4.63 yd³ | 63 bags |
| 1,000 ft² | 9.26 yd³ | 125 bags |
Should you order bulk mulch or bags?
Bulk mulch is often easier to price for larger, accessible projects. Bags can be easier to transport, stage, and spread in small or hard-to-reach beds. Compare the calculator's bulk and bag totals after adding delivery fees, minimum orders, tax, and the handling time for each option.
Can this calculator estimate bark or playground mulch?
Yes. Bark, wood chips, and playground surfacing use the same area-times-depth volume calculation. Enter the required installed depth and confirm compaction, fall-protection, and product-specific requirements with the supplier.
Material assumptions
- The starting bag size is 2 cubic feet and can be changed.
- Cost comparisons exclude tax, delivery, and minimum-order charges.
- Existing mulch is not subtracted.
- Depth is the finished, evenly spread layer.
Read the complete calculator methodology for unit conversions, rounding rules, and limitations.
Why the waste factor matters
A waste or extra-material percentage allows for real-world variation: irregular edges, cuts, compaction, settling, spillage, and measurement error. Ten percent is a useful starting point, not a universal rule. Increase or reduce it according to the material, layout, and supplier guidance.
Unit conversions used
Questions
Mulch Calculator FAQ
How deep should mulch be?
Two to three inches is common for established beds. Keep mulch away from trunks and stems, and follow local fire-safety guidance.
How many 2-cubic-foot bags equal one cubic yard?
A cubic yard contains 27 cubic feet, so it equals 13.5 two-cubic-foot bags. Since stores sell whole bags, round up to 14.
How many square feet does one cubic yard of mulch cover?
One cubic yard covers about 324 square feet at 1 inch deep, 162 square feet at 2 inches, 108 square feet at 3 inches, or 81 square feet at 4 inches, before any settling or extra-material allowance.
Can I use this as a bark or playground mulch calculator?
Yes. The volume calculation is the same for bark, wood chips, and playground surfacing. Enter the required depth and confirm compaction, fall-protection, and product-specific requirements with the supplier.
Should I remove old mulch first?
If the existing layer is still deep, measure it before adding more. Rake compacted material and avoid creating an excessively thick layer.