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Mulch Calculator

Enter the size of your beds and how deep you want the mulch to find the cubic yards for a bulk delivery or the number of bags to buy. It handles rectangular beds, circular tree rings and triangular corners.

Quick examples
%

Extra for compaction, spillage and uneven ground.

lb/ft³

Shredded wood mulch runs roughly 15–30 lb/ft³ depending on moisture.

$

Optional. Set to 0 to skip the cost.

Your numbers stay in your browser. Nothing is uploaded.
Volume needed1.17 yd³
Volume in cubic feet
31.5 cu ft
Estimated weight
0.31 ton
Area covered
120 ft²
Bags needed
16
Estimated cost
$72.00

Saved setups

Save a set of inputs you reuse — your usual rate, your loan, your room sizes — and load it back in one tap.

    Your recent calculations

    Results you calculate here are kept on this device so you can come back to them.

      Formula

      Volume (cu ft) = area (sq ft) × depth (in) ÷ 12 × (1 + waste %)
      Cubic yards = cubic feet ÷ 27
      Bags = cubic feet ÷ bag size, rounded up

      How to use it

      1. Choose the bed shape and enter its dimensions.
      2. Enter the mulch depth; 2–3 inches suits most beds.
      3. Pick your bag size, or switch the price to per cubic yard for bulk.
      4. Read the cubic yards and bag count.

      Worked examples

      A 30 × 4 ft bed mulched 3 inches deep, bought by the yard at $35

      Volume in cubic feet
      30 cu ft
      Volume needed
      1.11 yd³
      Bags needed
      15
      Estimated weight
      0.3 ton
      Estimated cost
      $38.89

      A 6 ft tree ring, 3 inches deep, in 2 cu ft bags at $4 each

      Volume in cubic feet
      7.07 cu ft
      Volume needed
      0.26 yd³
      Bags needed
      4
      Estimated cost
      $16.00

      How deep should mulch be?

      Use 2–3 in for most planting beds: enough to hold moisture and block weeds without smothering roots. Go to 3–4 in with coarse bark nuggets. When topping up an existing layer, 1 in is usually enough.

      Keep mulch a few inches away from tree trunks and plant stems. Piling it against the bark traps moisture and invites rot.

      Bags versus bulk

      One cubic yard equals 13.5 bags of the standard 2 cubic foot size. Bulk is usually cheaper once you need more than a yard or two, but bags are easier to carry to a back yard and leave nothing to shovel off the driveway.

      Questions people ask

      How many bags of mulch are in a yard?

      13.5 bags of 2 cubic feet each, so buy 14. For 3 cubic foot bags it is 9, and for 1.5 cubic foot bags it is 18.

      How much does a cubic yard of mulch cover?

      A cubic yard covers 162 sq ft at 2 in deep, 108 sq ft at 3 in and 81 sq ft at 4 in.

      How much mulch do I need for a 30×4 bed?

      At 3 in deep, a 30 × 4 ft bed needs 30 cubic feet: 15 bags of 2 cubic feet, or 1.11 cubic yards.

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