Mulch Calculator
Plan mulch for rectangular beds, circles and tree rings. Account for the layer already there, combine beds and compare whole bags with a bulk order.
Less guessing. Better garden planning.
View the formulas ↗Measure each bed
Choose a rectangle, circle, ring or known area. Use separate, non-overlapping shapes for irregular beds.
Count only added depth
Enter the target and existing layer. The calculator adds only the difference, never a negative volume.
Compare how to buy
Round to your bag size or bulk increment. Add your actual quotes and delivery charge to compare costs.
Small details. Better estimates.
Explore all 6 guides ↗From bed measurements to cubic yards of mulch
Calculate volume from area and depth, compare depth scenarios, and separate volume from your ordering allowance.
Read the guide ↗Guide 02 / Worked examplesMulch for round beds and tree rings
Use circle and ring geometry, distinguish radius from diameter, and leave excluded centers out of the volume.
Read the guide ↗Guide 03 / Worked examplesBagged versus bulk mulch: compare the quantities and full quoted cost
Compare whole bags against a supplier-specific bulk increment, including delivery, with hypothetical prices.
Read the guide ↗Guide 04 / Worked examplesHow much mulch to add when a bed already has a layer
Measure existing depth by section and calculate only the additional layer required for your selected target.
Read the guide ↗Guide 05 / Worked examplesMeasuring irregular garden beds without counting space twice
Split an L-shaped or tapered bed into simple pieces, account for exclusions, and combine volumes at different depths.
Read the guide ↗Guide 06 / Worked examplesMulch coverage, metric units and why yards are not tons
Convert volume and calculate coverage without confusing labelled bag volume with product weight.
Read the guide ↗Before you calculate
How many cubic feet are in a cubic yard?
Exactly 27. One cubic yard covers 108 ft² at a uniform depth of 3 inches before any allowance.
Do I add three inches every year?
Not automatically. Check the existing layer and use the depth appropriate for your material and plants. Excessive mulch can cause problems; keep it away from stems and trunks.
Can I calculate several beds?
Yes. Add a bed for every separate area and give each its own shape and target/existing depth. Avoid overlaps.
Can this convert mulch yards to tons?
No reliable weight follows from volume alone. Material, moisture and compaction change density. Ask the supplier for the specific product’s bulk density.