Mulch Calculator

Refreshing your garden beds? Enter the bed size and how deep you want the mulch to find how many bags of mulch you need — or how many cubic yards to order in bulk. Runs entirely in your browser.

📏 Bed length (feet)

Length

📐 Bed width (feet)

Width

📊 Mulch depth 2–4 inches is ideal for most beds

Inches

⚙️ Options

Bag size

Waste / overage (%) 5–10% is plenty

Bulk beats bags on big beds. One cubic yard equals 13.5 standard 2-cu-ft bags — if you need more than about 10 bags, bulk delivery is usually far cheaper per yard. Mulch settles around 10–15% in the first weeks, so a 3-inch layer is the sweet spot for weed suppression without suffocating plants.

Frequently Asked Questions

How many bags of mulch are in a cubic yard?

A cubic yard holds 27 cubic feet. A standard mulch bag is 2 cubic feet, so one cubic yard equals 13.5 bags. For 3-cu-ft bags, it's exactly 9 bags per yard.

How deep should mulch be?

Two to four inches is the ideal range for most garden beds: enough to suppress weeds and retain moisture, but not so deep that it suffocates roots. Three inches is the most common recommendation. Keep mulch a few inches away from tree trunks and plant stems.

How do I calculate mulch for a round bed?

For a circular bed, measure the diameter in feet, halve it for the radius, and use 3.14 × radius × radius for the area in square feet. Then multiply by depth (in feet) for cubic feet. As a shortcut: a 10-ft-diameter bed at 3 inches deep needs about 20 cubic feet — roughly 10 standard bags.

Is bulk mulch cheaper than bags?

Almost always, for larger jobs. Bulk mulch is sold by the cubic yard and typically costs far less per yard than the equivalent 13.5 bags. If your project needs more than about 10 bags, price out bulk delivery.

Is this calculator free?

Completely. No sign-up, no cookies, no servers — everything runs in your browser and your numbers never leave your device.