How much mulch do you need for 400 square feet?

Covering 400 square feet (for example a 40×10 ft bed) with mulch 3 inches deep takes 3.7 cubic yards — that's 50 bags of 2 cu ft or 34 bags of 3 cu ft. At 2 inches you need 2.47 yards.

Change the numbers

The calculator below is pre-filled for this project. Adjust any value — including feet and inches — and the results update instantly.

Several beds? Add up their square footage and use “Total area”.

Your results

Mulch needed3.7 cu yd

2 cu ft bags50

3 cu ft bags34

Cubic feet100 cu ft

One cubic yard covers108 sq ft at this depth

How much mulch do you need for 400 square feet — diagram

Mulch for 400 sq ft at every depth

Depth	Cubic yards	2 cu ft bags	3 cu ft bags
1 in	1.23	17	12
2 in	2.47	34	23
3 in	3.7	50	34
4 in	4.94	67	45

Bags or bulk?

At 3.7 cubic yards, buying bulk from a landscape yard is usually far cheaper than 50 bags. A full-size pickup bed typically holds 1.5–2 cubic yards of mulch, so delivery may be easier than hauling it yourself.

The math

400 sq ft × 3 in ÷ 12 = 100 cu ft 100 ÷ 27 = 3.7 cu yd 100 ÷ 2 cu ft = 50 bags (rounded up)

Common questions

How many bags of mulch for 400 square feet?

50 bags of 2 cu ft at 3 inches deep, or 34 bags at 2 inches.

How many yards of mulch for 400 square feet?

3.7 cubic yards at 3 inches, 2.47 at 2 inches.

Want the full method, tips and other sizes? See the mulch calculator guide.

Last reviewed November 1, 2026. Results are estimates — confirm with your supplier.

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