Mulch Calculator

How the Mulch Calculator Works

The math is volume = area × depth. Multiply your coverage area (length × width) by the depth, then convert units. Imperial: depth in inches divided by 12 gives feet, so area (sqft) × depth (ft) = volume in cubic feet. Divide by 27 to get cubic yards. Metric: depth in cm divided by 100 gives meters, so area (sqm) × depth (m) = cubic meters, or multiply by 1000 to get liters.

Mulch, topsoil, and gravel use the same volume formula but have different recommended depths and packaging. Mulch is typically applied 3-4 inches deep to suppress weeds and retain moisture. Topsoil is 2-3 inches for a top dressing or 6+ inches for new beds. Gravel is 2 inches for paths and 3-4 for drainage. Switch the material toggle above to update default depth and bag size.

For small projects, bags are convenient — a typical mulch bag is 2 cubic feet, topsoil 1 cu ft, gravel 0.5 cu ft (heavier). For projects over about 2 cubic yards (54 cu ft), bulk delivery by the cubic yard is usually 30-50% cheaper than bags, but you need somewhere to dump it. The calculator flags this threshold and shows both pricing paths so you can compare.

Practical workflow: measure your bed (length × width), pick depth based on material and purpose, choose bag size from a typical product, and enter both price-per-bag and price-per-cubic-yard if you can. The calculator computes both and tells you which is better. If you're also pouring concrete or laying tile in the same project, our concrete calculator and tile calculator complete the picture.