CalcWorks

Home › Landscaping

Mulch Calculator

Enter the area of your beds and the depth of mulch you want to get the volume in cubic yards for a bulk order, or the number of standard 2 cubic foot bags if you are buying from a store. Depth makes a bigger difference than most people expect — an extra inch across 200 square feet is another 8 bags.

Spreading bark mulch over a flower bed from a wheelbarrow
Quick start:
Cubic yards
— yd³
Cubic feet
— ft³
Bags (2 ft³ each)
—

Results update as you type. Estimates only — confirm final quantities before ordering.

The formula

Cubic feet = Area (ft²) × Depth (in) ÷ 12
Cubic yards = Cubic feet ÷ 27
Bags = Cubic feet ÷ 2 (standard bag size)

The 2 ft³ bag is the common US retail size for bagged mulch. One cubic yard equals 27 ft³, or 13.5 of those bags — the conversion to remember when comparing a bulk quote against bags.

Worked example

Example: 200 ft² of flower beds mulched 3 inches deep.

Reference chart

Mulch needed by area and depth
Area & depthCubic feetCubic yardsBags (2 ft³)
50 ft² @ 2 in8.30.315
50 ft² @ 3 in12.50.467
100 ft² @ 2 in16.70.629
100 ft² @ 3 in25.00.9313
100 ft² @ 4 in33.31.2317
200 ft² @ 3 in50.01.8525
500 ft² @ 3 in125.04.6363

Frequently asked questions

How deep should mulch be?

Two to four inches is the working range: 2–3 inches for refreshing existing beds, 3–4 inches for new beds and weed suppression. Keep mulch a few inches away from tree trunks and plant stems — piling it against bark ('mulch volcanoes') traps moisture and invites rot.

Is bulk mulch or bagged mulch cheaper?

At one cubic yard and up, bulk delivery is almost always cheaper per unit and produces far less plastic waste. Bags win for small beds, sloped sites a truck cannot reach, and jobs you want to spread over several weekends.

How many bags of mulch are in a cubic yard?

13.5 bags of the standard 2 ft³ size (27 ÷ 2). If your store sells 3 ft³ bags, it is 9 bags per yard — check the bag size before comparing prices.

Does mulch settle after spreading?

Yes — fresh mulch typically settles 10–20% in the first weeks as it compacts and begins to decompose. If an exact finished depth matters, order toward the top of the estimate.

Related calculators

Sources & method: Standard volume conversions (27 ft³ = 1 yd³); 2 ft³ retail bag size per major US brands (Scotts / Vigoro published packaging); cross-checked against Inch Calculator — Mulch Calculator.