Mulch Calculator
Estimate cubic yards and bags of mulch for a rectangular landscape bed.
Calculate your materials
Your estimate
Enter your measurements and select Calculate estimate to see the results.
Estimates are for planning only; verify product specifications and local requirements.
How this mulch calculator works
Mulch is sold loose by the cubic yard or in bags measured in cubic feet. This calculator lets you compare both. Bed dimensions and the intended mulch depth produce the volume; use your preferred bag size to estimate a bag count.
The calculation
Cubic feet = length × width × (depth ÷ 12). Cubic yards = cubic feet ÷ 27. Bags = round up(total cubic feet with extra allowance ÷ bag size).
Worked example
A 20 ft × 5 ft bed at 3 in deep holds 25 cu ft of mulch. With 5% extra, that is 0.97 cu yd, or 14 bags of 2 cu ft mulch.
Before buying materials
- Do not pile mulch against tree trunks or building siding.
- Measure each bed and add the volumes for several beds.
- Check actual bag volumes, because package sizes vary.
Frequently asked questions
How many cubic feet are in one cubic yard?
There are 27 cubic feet in one cubic yard.
Can I calculate several garden beds?
Yes. Calculate the beds one by one and add their volume estimates.
Is deeper mulch always better?
No. Appropriate depth depends on the material, plants and site conditions.