Free tool · for homeowners and landscapers
Mulch Calculator: How Much Mulch Do I Need?
Add every bed and tree ring, choose a depth, and get cubic yards for bulk delivery or the number of bags to buy. Compare bulk and bag prices in one place. Works for topsoil and compost too.
Mulch Calculator
- Bed 180 sq ft
Works the same for topsoil, compost and decorative stone by volume. University extension services recommend 2 to 4 inches of mulch, kept a few inches away from tree trunks and stems.
How Much Mulch Do I Need?
Multiply the bed area in square feet by the depth in inches and divide by 324 to get cubic yards. A 200-square-foot bed at 3 inches deep needs about 1.85 cubic yards, or 25 bags of 2 cubic feet. Most beds need 2 to 4 inches, kept away from tree trunks.
Checked against the sources below · How we build and test our calculators
Mulch Coverage Chart
How far one cubic yard goes, and bags needed per 100 sq ft.
| Depth | 1 cu yd covers | Cu yd per 100 sq ft | 2 cu ft bags per 100 sq ft | 3 cu ft bags per 100 sq ft |
|---|---|---|---|---|
| 1 in | 324 sq ft | 0.31 | 5 | 3 |
| 2 in | 162 sq ft | 0.62 | 9 | 6 |
| 3 in | 108 sq ft | 0.93 | 13 | 9 |
| 4 in | 81 sq ft | 1.23 | 17 | 12 |
| 5 in | 64.8 sq ft | 1.54 | 21 | 14 |
| 6 in | 54 sq ft | 1.85 | 25 | 17 |
How to Measure Your Beds
- Rectangles: length × width.
- Tree rings: measure across the circle (the diameter).
- Curvy beds: split them into rectangles and triangles, or pace out the area and enter it directly.
- Subtract large stones, patios or shrubs the mulch won’t cover by leaving them out.
Mulching Tips
- Don’t build “mulch volcanoes” against tree trunks; it invites rot and pests.
- Top up, don’t pile on: check the old layer and add only enough to reach 2 to 4 inches.
- Order a little extra for settling; fresh mulch compacts.
Add This Calculator to Your Website, Free
Landscape suppliers and lawn companies: let customers work out their order on your site, in your colors, with a button to order delivery.
Paste it into any page of your website as an “HTML” or “embed” block. It’s free, needs no account and collects no visitor data.
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Questions
How much mulch do I need?
Multiply the bed area in square feet by the depth in inches, divide by 12 to get cubic feet, then by 27 for cubic yards. A 200 sq ft bed at 3 inches is 200 × 3 ÷ 12 = 50 cu ft, or about 1.85 cubic yards.
How many bags of mulch are in a yard?
A cubic yard is 27 cubic feet, so it takes 13.5 bags of 2 cu ft (round up to 14), 9 bags of 3 cu ft, or 18 bags of 1.5 cu ft.
How deep should mulch be?
University of Illinois Extension recommends 2 to 4 inches: 2 to 3 inches for fine or composted mulch and 3 to 4 inches for coarse mulch. Keep it at least 4 inches away from tree trunks.
How many square feet does a yard of mulch cover?
One cubic yard covers 324 sq ft at 1 inch deep, 162 sq ft at 2 inches, 108 sq ft at 3 inches and 81 sq ft at 4 inches.
Is bulk mulch cheaper than bags?
For more than a couple of cubic yards, bulk delivery from a landscape supplier is usually cheaper per yard than bags, and saves plastic. Bags are easier for small beds or where a truck can’t reach. Enter both prices to compare.
Does this work for topsoil, compost or gravel?
Yes for volume: cubic yards and bags work the same for any material. Gravel and stone are often sold by the ton; ask your supplier how many tons make a cubic yard of the product you choose.