Mulch Calculator
Measure your bed, pick a depth, and get the mulch you need in cubic yards for bulk delivery or bag counts for the garden center run.
Cubic yards
0.93
Cubic feet
25.0
2 cu ft bags
13
3 cu ft bags
9
One cubic yard covers 162 sq ft at 2" deep, 108 sq ft at 3", or 81 sq ft at 4". For several beds, run each one and add the yards — and keep mulch a few inches back from trunks and stems rather than piling it against them.
How Mulch Math Works
Mulch is volume: bed area in square feet times depth converted to feet. Bulk mulch is sold by the cubic yard (27 cubic feet) and bagged mulch most commonly in 2 cubic foot bags — so a cubic yard equals 13.5 of those bags, which is why bulk wins on price for anything beyond a couple of beds.
Formula
Cubic yards = (area sq ft × depth in ÷ 12) ÷ 27 Coverage per cubic yard: 2" deep → 162 sq ft 3" deep → 108 sq ft 4" deep → 81 sq ft Example: 20×5 ft bed at 3": 100 × 0.25 = 25 cu ft = 0.93 cu yd ≈ 13 two-cu-ft bags
Frequently Asked Questions
How much does a cubic yard of mulch cover?
162 sq ft at 2 inches deep, 108 sq ft at 3 inches, or 81 sq ft at 4 inches. The math: a cubic yard is 27 cubic feet, so divide 27 by the depth in feet. Mulch is one of the few materials where a pickup truck bed (roughly 2 yards heaped) genuinely handles a typical yard's worth.
How many bags of mulch are in a cubic yard?
13.5 of the standard 2-cubic-foot bags, or 9 of the 3-cubic-foot bags. That conversion is also the price check: multiply the per-bag price by 13.5 and compare it to the bulk per-yard price — bulk usually wins by a wide margin once you need more than a yard.
How deep should mulch be?
2–3 inches for most beds — enough to suppress weeds and hold moisture without smothering roots. Go thinner (1–2") around shallow-rooted perennials, and never pile it against trunks: the 'mulch volcano' around a tree traps moisture against bark and invites rot. Leave a few inches of bare ground at the stem.
Should I buy mulch in bags or in bulk?
Bulk for anything over about a cubic yard — it typically costs half as much per yard as bagged. Bags win for small jobs, tight access, staying dry in storage, and not needing a delivery fee or a truck. Many suppliers have a 1–2 yard delivery minimum, which is the practical crossover point.