Mulch Calculator

Estimate mulch by bags, cubic yards, cubic meters, and cubic feet. The calculator works with imperial beds measured in feet and inches or metric beds measured in meters and centimeters, then converts everything to cubic feet for bag counts.

How to use this calculator

Choose imperial or metric. Enter bed length, width, and desired depth, then choose 2 cu ft or 3 cu ft bags. The primary result is number of bags, with cubic yards, cubic meters, and cubic feet listed below.

Formula

For imperial measurements:

$cubic\ feet = length\ in\ ft \times width\ in\ ft \times depth\ in\ inches \div 12$

A 12 ft by 8 ft bed at 3 inches deep needs 24 cu ft. That is 0.89 cu yd, 0.68 m³, or 12 bags when using 2 cu ft bags. If the bed has curves, split it into rectangles, estimate each section, and add the totals before ordering.

Mulch depth tips

Avoid piling mulch against trunks, stems, or siding. If you are building up planting beds, estimate soil separately with the topsoil calculator. For organic amendment before mulching, use the compost calculator. For large rectangular beds, double-check the footprint with the square footage calculator.