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Mulch Calculator

Quick answer: Mulch volume is bed area × depth. Most beds get 2 to 3 inches. A 20 × 10 ft bed at 3 inches needs about 1.85 cubic yards, which is about 25 bags of 2 cubic feet. Enter your bed dimensions below; measure irregular beds as a few rectangles and add them up.

How the estimate works

The tool returns cubic yards for bulk orders and a bag count for retail bags. Bag sizes are commonly 2 or 3 cubic feet, while bulk mulch is sold by the yard. Topping up an existing layer needs only the difference between the current and target depth, so measure what is already there before ordering.

Worked example: mulch calculator

Illustrative examples (2026-10-29), not quotes or guarantees.

Three beds of 12 × 4 ft = 144 ft². At 3 in: 36 ft³ ≈ 1.33 yd³, or 18 bags of 2 ft³. Topping up from 1 in to 3 in needs only 2 in: 24 ft³ ≈ 12 bags.

FAQ

How deep should mulch be?

Usually 2–3 in; see mulch depth.

Bags or bulk?

Compare with the bags vs bulk calculator.

How do I measure a round bed?

Area = 3.14 × radius². Enter that number as length and 1 as width.

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