Gravel Cost Calculator

Mulch Calculator

Estimate how many cubic yards or bags of mulch you need for a garden bed or landscaping area based on size and depth.

Pick the shape that best matches your garden bed or landscaping area.

ft
ft
in

Most garden beds use 2–3 in of mulch depth.

Covers settling, uneven ground, and spillage. 10% works for most garden beds.

How this is calculated

Area is calculated from the shape you select — rectangle (length × width), circle (π × radius²), triangle (½ × base × height), circular ring (π × (outer radius² − inner radius²)) for a mulch ring around a tree, or trapezoid (average of the two parallel sides × width). That area is multiplied by depth to get the exact volume required, converted from cubic feet to cubic yards (27 ft³ per yd³). Your selected waste percentage is added to cover settling, uneven ground, and spillage, and weight and bag count are both calculated from that same waste-adjusted volume — weight assumes standard shredded bark mulch at approximately 500 lb per cubic yard (actual density varies with moisture and mulch type), and the bag estimate assumes standard 2 cubic foot bags. The suggested order then rounds that waste-adjusted volume up to the nearest 0.1 yd³ for bulk delivery.

Example calculation

A 15 ft × 8 ft garden bed at 3 in deep needs 1.11 yd³ of mulch. With 10% waste that's 1.22 yd³ — about 611 lb, or 17 bags of 2 ft³ mulch — so suggested order is 1.3 yd³ in bulk.

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Frequently asked questions

Yes. Use the "Bed shape" dropdown to switch to circle, triangle, circular ring (for a mulch ring around a tree), or trapezoid. Each shape shows the measurements it needs and the area formula used is shown in the breakdown.