Mulch Calculator
Enter your beds and depth to see how many cubic yards or bags of mulch to buy.
Typical depths for mulch
| Job | Typical depth |
|---|---|
| Most garden beds | 2–4 in (keep it pulled back from stems and trunks) |
| Topping up last year's mulch | 1–2 in |
| Paths | 3–4 in |
Typical ranges, not specifications. Follow your project's plans or local requirements where they apply.
How much does a cubic yard of mulch cover?
One cubic yard is 27 cubic feet. Spread it 1 inch deep and it covers 324 square feet. Every extra inch of depth cuts the coverage proportionally. A cubic yard of mulch weighs about 0.3 tons.
| Depth | 1 cubic yard covers |
|---|---|
| 1 in | 324 sq ft |
| 2 in | 162 sq ft |
| 3 in | 108 sq ft |
| 4 in | 81 sq ft |
| 6 in | 54 sq ft |
How the mulch calculator works
Area = length × width (circle: π × radius²; triangle: base × height ÷ 2)
Cubic feet = area × (depth in inches ÷ 12)
Cubic yards = cubic feet ÷ 27
Tons = cubic yards × weight per cubic yard ÷ 2,000
Worked example: a 12 × 8 ft bed, 3 in deep
Area: 12 × 8 = 96 sq ft. Volume: 96 × (3 ÷ 12) = 24 cubic feet. Cubic yards: 24 ÷ 27 = 0.89 cubic yards, which weighs about 0.27 tons at 600 lb per cubic yard.
Adding 10% for settling brings it to 0.98 cubic yards, about 0.29 tons. Mulch is usually sold by the cubic yard or by the bag.
Tips before you order
- Bagged mulch is sold by volume. A 2 cu ft bag is the most common size.
- Thicker isn't better: deep layers can keep water and air from the soil.
- Bulk mulch by the cubic yard is usually cheaper once you need more than a yard or two.
Questions people ask
How much does a cubic yard of mulch weigh?
About 0.3 tons (600 lb) is a typical figure. Most mulch weighs 400–800 lb per cubic yard, depending on the material and how wet it is. Your supplier can tell you the weight of theirs.
How many square feet does a yard of mulch cover?
One cubic yard covers 162 sq ft at 2 inches deep, 108 sq ft at 3 inches and 81 sq ft at 4 inches. The rule: 324 ÷ depth in inches.
How do I convert cubic yards of mulch to tons?
Multiply cubic yards by the weight per cubic yard and divide by 2,000. At 600 lb per yard, that's cubic yards × 0.3.
How many 2 cu ft bags of mulch are in a cubic yard?
About 13.5 2 cu ft bags make one cubic yard (by volume).
How many 3 cu ft bags of mulch are in a cubic yard?
About 9 3 cu ft bags make one cubic yard (by volume).
How much mulch do I need for a 12 × 8 ft bed, 3 in deep?
About 0.89 cubic yards (about 0.27 tons), or 0.98 cubic yards with 10% extra for settling.