Sometimes the question is not how much mulch to buy but how far the mulch you have will go. This page gives a ready-made coverage chart for the common bag sizes and for a cubic yard at depths from 1 to 6 inches, and the calculator above works out the coverage for any amount you enter — a pile left over from last season, a pallet of bags or a bulk delivery.
How to use the mulch coverage calculator
- Enter the amount of mulch and choose its unit: bags of 1, 1.5, 2 or 3 cubic feet, cubic yards or cubic feet.
- Enter the depth you plan to spread it.
- Read the area covered in square feet, square meters and square yards. The tables underneath repeat the result at other depths and show the full chart.
Coverage formula
Coverage is volume divided by depth. With volume in cubic feet and depth in inches:
For a cubic yard, the volume is 27 ft³, so the area is 324 ÷ depth in inches.
Mulch coverage chart
Square feet covered by one bag or one cubic yard:
| Depth | 1 cu ft bag | 1.5 cu ft bag | 2 cu ft bag | 3 cu ft bag | 1 cubic yard |
|---|---|---|---|---|---|
| 1 in | 12 | 18 | 24 | 36 | 324 |
| 2 in | 6 | 9 | 12 | 18 | 162 |
| 3 in | 4 | 6 | 8 | 12 | 108 |
| 4 in | 3 | 4.5 | 6 | 9 | 81 |
| 5 in | 2.4 | 3.6 | 4.8 | 7.2 | 64.8 |
| 6 in | 2 | 3 | 4 | 6 | 54 |
Worked examples
Ten 2 cu ft bags at 3 inches: 10 × 2 = 20 ft³; 20 × 12 ÷ 3 = 80 ft² — enough for a bed about 6.3 × 12.6 ft.
A 3-yard delivery at 2 inches: 3 × 27 = 81 ft³; 81 × 12 ÷ 2 = 486 ft².
The same 3 yards at 4 inches covers only 243 ft². Doubling the depth halves the coverage.
Reading bag labels
Most bagged mulch in the US is sold by volume in cubic feet: 2 cu ft is the most common size, with 1.5 and 3 cu ft bags also widespread. Some brands list liters instead. A 56.6-liter bag is the metric label for 2 cubic feet, and a 50-liter bag holds about 1.77 cubic feet. When a bag is labeled in liters, divide by 28.32 to get cubic feet before using the chart. Bags of rubber or stone mulch are usually labeled by weight, which this chart does not cover — check the package for a coverage figure.
Why real coverage differs from the chart
The numbers above describe an idealized layer of exactly even depth. In practice:
- Settling. Freshly spread shredded mulch can compact by a quarter to a third after rain, so a 3-inch layer may end up closer to 2 inches.
- Texture. Coarse nuggets leave air gaps and look thinner than fine mulch at the same depth, so people tend to spread them more thickly.
- Uneven ground. Dips, roots and edging all trap extra mulch.
- Existing mulch. If an inch of old mulch remains, you only need to add enough to reach your target depth, which stretches coverage considerably.
For planning a new purchase from bed dimensions, including bag-versus-bulk costs, use the mulch calculator.
Frequently asked questions
How many square feet does a bag of mulch cover?
A standard 2 cubic foot bag covers 24 square feet at 1 inch deep, 12 square feet at 2 inches and 8 square feet at 3 inches. A 3 cubic foot bag covers half again as much: 18 square feet at 2 inches and 12 at 3 inches.
How much area does one cubic yard of mulch cover?
324 square feet at 1 inch, 162 at 2 inches, 108 at 3 inches and 81 at 4 inches. Divide 324 by your depth in inches to get the figure for any depth.
How many bags of mulch do I need for a 10 × 10 bed?
A 10 × 10 bed is 100 square feet. At 3 inches deep that is 25 cubic feet, or 12.5 bags of 2 cubic feet — buy 13. At 2 inches you would need about 8⅓, so 9 bags.
Why didn't my mulch cover as much as the chart says?
Charts assume a perfectly even layer on flat ground. Mulch fluffs up when first spread and then settles, beds are rarely level, and people tend to spread more thickly near edges and plants. Buying about 10% more than the chart suggests covers those differences.