Landscape & Outdoor

Mulch Calculator – Cubic Yards & Bags

Estimate mulch for rectangular landscape beds and convert the result into cubic yards and common bag counts.

Updated: August 30, 2026 · Published by BetterHomeHabits

Quick answer

A 20 × 8 ft bed at 3 inches deep requires about 40 cubic feet, or roughly 1.5 cubic yards.

Purpose
Calculate mulch volume in cubic yards, cubic feet and bags from bed area and depth.
Formula
Cubic feet = length × width × depth in feet. Cubic yards = cubic feet ÷ 27. Bags = cubic feet ÷ bag volume.

How this calculator works

Estimate mulch for rectangular landscape beds and convert the result into cubic yards and common bag counts.

Formula
Cubic feet = length × width × depth in feet. Cubic yards = cubic feet ÷ 27. Bags = cubic feet ÷ bag volume.

Example

A 20 × 8 ft bed at 3 inches deep requires about 40 cubic feet, or roughly 1.5 cubic yards.

How to get a better estimate

  • Refresh beds often need less depth than new beds.
  • Measure separate beds and add their totals.
  • Bulk yards are usually easier for larger projects.

What the result means

The result is a planning estimate. Dimensions, coverage, density, packaging and installation conditions vary by product and project. For purchasing, compare the result with the exact product label or supplier specification. For structural, electrical, code-regulated or safety-critical work, use an appropriately qualified professional.

Common questions about the Mulch Calculator

What does this calculator estimate?

Estimate mulch for rectangular landscape beds and convert the result into cubic yards and common bag counts.

What formula does it use?

Cubic feet = length × width × depth in feet. Cubic yards = cubic feet ÷ 27. Bags = cubic feet ÷ bag volume.

How should I use the result?

Use it as a planning estimate, then verify the dimensions and replace editable defaults with the specifications for the product or service you actually intend to buy.

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