How far will my mulch go?
Enter how many bags or yards you have and how deep you want it.
How the mulch calculator works
The calculator finds the area of each shape, multiplies by how many you have, subtracts cut-outs such as tree trunks and paving, then multiplies by the depth. It adds your extra allowance and converts to cubic yards, cubic meters and liters. Bag counts, weight, loads and cost all come from that one volume.
With extra = volume × (1 + extra %)
Cubic yards = cubic feet ÷ 27
Bags = cubic feet ÷ bag size, rounded up
Area formulas used for each shape
| Shape | Formula |
|---|---|
| Rectangle | length × width |
| Circle | π × (diameter ÷ 2)² |
| Triangle | ½ × base × height |
| Known area | entered directly in sq ft (or sq m if you chose meters) |
Worked examples
Example 1: a 10 × 4 ft bed, 3 inches deep
10 × 4 = 40 sq ft. At 3 in (¼ ft) deep that is 10 cu ft, or 11 cu ft with 10% extra. That is 0.41 cubic yards, or 6 bags of 2 cu ft (5.5 rounded up).
Example 2: a round bed around a tree, 8 ft across with a 2 ft trunk area
Bed area = π × 4² = 50.3 sq ft. Enter the 2 ft trunk area as a cut-out: π × 1² = 3.1 sq ft. Net area is 47.1 sq ft. At 3 in deep that is 11.8 cu ft, or 13.0 cu ft with 10% extra, which is 0.48 cubic yards or 7 bags of 2 cu ft.
Example 3: 600 sq ft of front beds, 3 inches deep
600 sq ft × ¼ ft = 150 cu ft, or 165 cu ft with 10% extra. That is 6.1 cubic yards, so order 6.25 yd³ in bulk. The same job in bags would be 83 bags of 2 cu ft, so bulk is worth pricing for jobs this size.
How far does a cubic yard of mulch go?
| Depth | Area covered by 1 cubic yard |
|---|---|
| 1 in | 324 sq ft |
| 2 in | 162 sq ft |
| 3 in | 108 sq ft |
| 4 in | 81 sq ft |
These are before the extra allowance. Divide 324 by the depth in inches for a quick estimate.
How many bags in a cubic yard?
| Bag size | Bags per cubic yard |
|---|---|
| 1 cu ft | 27 |
| 1.5 cu ft | 18 |
| 2 cu ft | 14 (13.5, rounded up) |
| 3 cu ft | 9 |
Check the size on the bag, because some brands sell in liters or odd sizes.
Mistakes to avoid
- Piling mulch against trunks and stems. Leave a gap so the bark and stems stay dry. The calculator's cut-out option is handy for this.
- Going too thick. More is not always better. Stay in the 2 to 4 inch range unless your supplier advises otherwise.
- Mixing up depth units. 3 inches is ¼ foot, not 3. Pick the depth unit in the tool and check the result looks sensible.
- Ordering by bag for large jobs. Past a few cubic yards, bulk is often much cheaper. Compare both prices above.
- Forgetting the extra. Mulch spills, thins out over uneven ground and settles. A 10% buffer avoids a second trip.
How far do bags of mulch go?
This table uses 2 cubic foot bags, the most common size. Mulch is usually spread 2 to 4 inches deep.
| You have | Covers at 2 in deep | Covers at 3 in deep | Covers at 4 in deep |
|---|---|---|---|
| 10 bags (2 cu ft each) | 120 sq ft | 80 sq ft | 60 sq ft |
| 20 bags | 240 sq ft | 160 sq ft | 120 sq ft |
| 25 bags | 300 sq ft | 200 sq ft | 150 sq ft |
| 50 bags | 600 sq ft | 400 sq ft | 300 sq ft |
| 1 cubic yard | 162 sq ft | 108 sq ft | 81 sq ft |
| 2 cubic yards | 324 sq ft | 216 sq ft | 162 sq ft |
Round bag counts up and add about 10% for uneven ground and spillage.
Frequently asked questions
How many bags of mulch are in a cubic yard?
A cubic yard is 27 cubic feet, which is 13.5 bags of 2 cubic feet, so plan on 14. It is 18 bags of 1.5 cubic feet, 27 bags of 1 cubic foot, or 9 bags of 3 cubic feet.
How deep should mulch be?
A common range is 2 to 4 inches. Use the thinner end for fine mulch and small plants and the thicker end for coarse mulch in new beds. Keep mulch off tree trunks and plant stems, and check what your plants prefer.
How much does a cubic yard of mulch weigh?
Bulk wood mulch is commonly quoted at roughly 400 to 800 pounds per cubic yard, depending on the type and how wet it is. Bagged mulch is often lighter per cubic foot. The calculator uses 20 pounds per cubic foot (about 540 per yard), and you can change it.
Is bulk or bagged mulch cheaper?
For larger areas bulk is usually cheaper per cubic foot, but suppliers often add a delivery fee or set a minimum order. Bags suit small beds. Enter both prices in the calculator to compare for your own project.
How much extra mulch should I buy?
About 10% extra covers uneven ground, spillage and thin spots. The calculator adds 10% by default, and you can set it from 0 to 20%.
How many square feet does a cubic yard of mulch cover?
At 3 inches deep one cubic yard covers about 108 square feet. At 2 inches it covers about 162 square feet, and at 4 inches about 81 square feet.
What is the 3-3-3 rule for mulch?
It is a rule of thumb. People usually describe it as about 3 inches of mulch, kept about 3 inches back from the trunk or stems, spread in a ring around 3 feet across for a new tree. Versions differ slightly, so treat it as a guide and check what your plants prefer.
How many bags of mulch do I need for 100 square feet?
At 3 inches deep, 100 square feet needs 25 cubic feet, which is 13 bags of 2 cubic feet. At 2 inches it is 17 cubic feet, so 9 bags, and at 4 inches it is 33 cubic feet, so 17 bags. A 10 by 10 foot bed is 100 square feet.
How much will 20 bags of mulch cover?
20 bags of 2 cubic feet is 40 cubic feet. That covers about 240 square feet at 2 inches deep, 160 square feet at 3 inches and 120 square feet at 4 inches. For 10 bags, halve those numbers, and for 25 bags multiply them by 1.25.
How much will 25 bags of mulch cover?
25 bags of 2 cubic feet is 50 cubic feet. That covers about 300 square feet at 2 inches, 200 square feet at 3 inches and 150 square feet at 4 inches.
What is a common mistake when applying mulch?
Piling it against tree trunks and plant stems, often called a mulch volcano, which holds moisture against the bark and invites rot and pests. Other common mistakes are spreading it too thick, which can keep water from reaching roots, and not topping it up as it breaks down.
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