Mulch Calculator: How Much Mulch Do I Need?
Enter the landscaping area and mulch depth. You will get the exact cubic yards, a sensible bulk purchase amount, common bag equivalents, and optional cost.
Project measurements
Use dimensions or enter the total area if you already measured it.
How much mulch do I need?
Multiply the area you want to cover by the mulch depth, then convert the volume to cubic yards. This calculator does the conversion and translates the same amount into common bag sizes so the answer is useful whether you are ordering bulk mulch or buying bags.
Depth is measured after the mulch settles. If you are topping up an existing bed, measure the extra depth you want to add rather than the finished total.
What depth should I use?
| Depth | Typical use | 1 cubic yard covers |
|---|---|---|
| 1 inch | Very light refresh | about 324 sq ft |
| 2 inches | Refresh existing beds | about 162 sq ft |
| 3 inches | Common general coverage | about 108 sq ft |
| 4 inches | Deeper coverage | about 81 sq ft |
Coverage is 324 ÷ depth in inches, because one cubic yard spread one inch deep covers 324 square feet.
How to measure a mulch bed
Feet are easiest for most U.S. landscaping projects.
For irregular beds, split the bed into simple rectangles instead of forcing one rough measurement.
Depth has a big effect. Four inches takes twice as much mulch as two inches.
For an irregular bed, break it into rectangles and add each one with + Add another area. The calculator sums every area before converting and rounding, so splitting a bed never changes the answer.
Cubic yards or bags?
Bulk mulch is usually cheaper per cubic yard once you need more than about two yards, but it has to be delivered or hauled and moved by wheelbarrow. Bags are easier for small beds and for anything you cannot get a truck near. The result shows both so you can compare against real prices — check whether a bag is 2 or 3 cubic feet before comparing, because the difference is 50%.
Common mistakes
- Entering inches as feet for mulch depth.
- Rounding measurements down before calculating.
- Buying the exact mathematical volume with no allowance for uneven grade or settling.
- Comparing bag prices without checking whether the bag is 2 or 3 cubic feet.
Building the bed from scratch?
Estimate the soil layer underneath before you order mulch.
Open the Topsoil Calculator →