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Landscape & Aggregates

Mulch Calculator

This mulch calculator tells you how many cubic yards or bags to buy for your beds; see our yard drainage guide for grading around beds. Mulch is sold in bulk by the cubic yard or in bags of 2 or 3 cubic feet. Measure your beds, choose a depth — 2–3 inches is common for refreshing beds, 3–4 inches for new ones — and get both bulk and bag quantities.

Results from this mulch calculator are planning estimates; confirm quantities and prices with your supplier or contractor before you order.

Enter your project

ft
in
m
ft
in
m
in
cm
$/yd³
$/bag

Results

Your results will appear here

Enter your measurements and press Calculate. Defaults show a typical example.

How to use the mulch calculator

  1. Measure each bed; use the circle option for tree rings.
  2. Choose a depth (2–3 in to top up, 3–4 in for new beds).
  3. Compare bulk and bagged pricing.

Formula

Cubic yards = area (sq ft) × depth (in) ÷ 324. Bags = cubic feet ÷ bag size.

Worked example

A 20 × 5 ft bed at 3 in: 100 × 3 ÷ 324 = 0.93 yd³, or 13 bags of 2 cu ft.

Tips for using the mulch calculator

  • Spread 2–3 in to refresh beds and 3–4 in for new beds; deeper mulch can starve roots of air.
  • Keep mulch a few inches away from tree trunks and house siding.
  • Bulk mulch is usually cheaper than bags once you need more than about 2–3 yards.
  • Remove weeds and edge your beds before spreading mulch; mulch suppresses new weeds but will not smother established ones, and clean edges keep it from washing onto lawns and walks. Water the mulch lightly after spreading to help it settle in place.
Dry-stacked fieldstone garden wall with potted plants at its base

Mulch Calculator FAQs

How many bags of mulch in a yard?

13.5 two-cubic-foot bags or 9 three-cubic-foot bags.

How deep should mulch be?

Commonly 2–4 in. Keep mulch pulled back a few inches from tree trunks and house siding.

How much area does a yard of mulch cover?

About 108 sq ft at 3 in deep, or 162 sq ft at 2 in.

Estimate before you call a contractor

Run the numbers with our free calculators so you can compare bids with confidence.