Mulch Calculator
Convert bed size or square footage into cubic yards and bags - then compare bagged vs bulk pricing before spring planting season.
Mulch needed
0.37 cubic yards
10 cubic feet · each 2 cu ft bag covers about 8 sq ft at this depth
- 2 cu ft bags
- 5
- With 5% waste
- 6
- Bagged cost
- $23.82
- Bulk yard cost
- $17.50
For larger beds, bulk mulch by the cubic yard is usually cheaper than bags. 2–3 inches is typical for new beds; 1–2 inches for a seasonal top-up.
How the mulch formula works
Mulch volume is area × depth. Enter length and width, or total square footage, then choose how deep you want the layer:
cubic feet = square feet × (depth inches ÷ 12)
Divide by 27 for cubic yards (what bulk suppliers sell). For bags, divide cubic feet by the bag size - usually 2 or 3 cubic feet - and round up.
Example: a 500 sq ft bed at 2 inches needs 83.33 cubic feet, or 3.086 cubic yards. That's 42 bags of 2 cu ft mulch before waste, or about 44 bags with a 5% buffer.
- Use 2–3" for new beds
- Use 1–2" for a yearly refresh
- Switch to bulk once you pass ~1 cubic yard
Irregular beds? Break them into rectangles, add the areas, then run the total square footage through the calculator.
Frequently asked questions
How do I calculate how much mulch I need?
Multiply the bed’s square footage by depth in feet (inches ÷ 12) to get cubic feet, then divide by 27 for cubic yards. Divide cubic feet by 2 or 3 to estimate bag counts for common bag sizes.
How many bags of mulch for 500 square feet?
At 2 inches deep, 500 sq ft needs about 83 cubic feet - roughly 42 bags of 2 cu ft mulch (or 28 bags of 3 cu ft) before waste. At 3 inches, plan on about 63 of the 2 cu ft bags.
How deep should mulch be?
New beds usually get 2–3 inches. A seasonal refresh is often 1–2 inches. Keep mulch a few inches away from tree trunks and plant stems to avoid rot.
Is bulk mulch cheaper than bags?
Usually yes once you need more than about 1 cubic yard. Bags are convenient for small beds and touch-ups; bulk delivery wins for large landscaping jobs.
How many square feet does a 2 cu ft bag cover?
At 2 inches deep, about 12 sq ft. At 3 inches deep, about 8 sq ft. Coverage drops as depth increases because the same bag volume is spread thicker.
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