Mulch Calculator

Enter your bed dimensions and desired depth. Get cubic yards and bag count instantly.

Mulch Calculator
✓ Your estimate
Estimated mulch needed
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Cubic Yards
Switch display unit only.
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Cubic Yards
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Cubic Feet
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3 cu ft Bags
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Calculate first to see unit conversions.

What this estimate includes

This estimate shows mulch needed in cubic yards, cubic feet, and bags based on your bed size, depth, and bag size.

How it’s calculated

Area = length × width
Volume = area × depth
Cubic yards = cubic feet ÷ 27
Bags = cubic feet ÷ bag size

Before you order

Bed shape, existing mulch depth, settling, and product size can change the final quantity. Use this as a planning estimate and confirm with your landscape supplier before ordering.

Frequently Asked Questions

How deep should mulch be?
2 inches is right for refreshing existing mulch. 3 inches is standard for a new bed. 4 inches for heavy weed suppression. Do not exceed 4 inches around plants -- thick mulch can mat down and prevent water from reaching roots.
How many bags of mulch equal one cubic yard?
One cubic yard equals 27 cubic feet. A 3 cubic foot bag requires 9 bags per cubic yard. A 2 cubic foot bag requires about 14 bags per cubic yard. Use the calculator above for your exact area and depth.
Is bulk mulch cheaper than bags?
For anything over 2-3 cubic yards, bulk delivery is almost always cheaper. A cubic yard of bulk hardwood mulch typically costs $30-60 depending on your region. The equivalent in bags at retail prices is usually 2-3 times more expensive.
How much mulch do I need around trees?
Apply 3 inches of mulch in a ring around trees, keeping it 2-3 inches away from the trunk. Extend the ring as wide as the drip line (outer edge of canopy) if possible. Never pile mulch against the trunk -- this traps moisture, causes rot, and invites pests.
Can too much mulch hurt plants?
Yes. More than 4 inches of mulch can mat down and block water and air from reaching roots. Piling mulch against tree trunks (called volcano mulching) traps moisture, causes bark rot, and creates habitat for pests and disease.
Should I remove old mulch before adding new?
Not usually. If existing mulch is under 3 inches, top-dress with 1-2 inches of fresh mulch. If it is over 4 inches deep, rake out the old layer first -- excessive mulch depth blocks water and oxygen from reaching plant roots.
When is the best time to mulch?
Spring after soil warms and fall before frost are the best times. Spring mulching retains moisture and suppresses summer weeds. Fall mulching insulates roots from freeze-thaw cycles. Avoid mulching when soil is frozen or waterlogged.
Disclaimer: This calculator provides estimates only. Actual quantities depend on bed shape, existing mulch depth, and material density. Verify with your landscape supplier before ordering bulk delivery. See all outdoor material calculators.