Mulch Calculator
Size hardwood or bark mulch for beds and tree rings. See cubic yards, bags, and weight with a default 10% settling allowance you can change.
Formula example
A 100 ft² bed at 3 in deep, with 10% settling and hardwood mulch at 20 lb/ft³ needs 1.02 yd³ to buy (27.50 ft³). That is about 0.28 US tons, 550 lb, and 14 bags at 2 ft³ each. Many suppliers round bulk orders to the next 0.5 yd³, which would be 1.50 yd³ on this job.
Material densities
Default dry densities come from published soil and aggregate references. You can override density in the calculator when your supplier quotes a different number.
| Material | lb/ft³ | ton/yd³ |
|---|---|---|
| Shredded hardwood mulch | 20 | 0.27 |
| Cedar mulch | 17 | 0.23 |
| Pine bark nuggets | 13 | 0.18 |
Measuring mulch beds
Stretch a tape along the outside edge of the bed or use a plat dimension for irregular shapes via Area (ft²). For tree rings, measure the outer diameter and subtract the trunk opening with deduct square feet if you only mulch the donut.
Keep depth consistent with how you will spread: fluffier mulch may settle within a few weeks, which is why the default waste field is labeled as settling.
Bag versus bulk
Two-cubic-foot bags are common at garden centers. Bulk cubic yards are usually cheaper for large jobs but need a tarp and edge restraint. The shopping list shows both so you can compare quotes.
FAQ
Why is 2–4 inches the usual mulch depth?
That range covers weed suppression and moisture without smothering plant crowns. The calculator shows an info note when depth is under 2 in or over 4 in so you can double-check the plan.
How do 2 ft³ bags compare with bulk yards?
Bag count divides purchase cubic feet by the bag size you enter, rounding up. Bulk yards use the same engine volume; the default 100 ft² bed at 3 in with 10% settling is 1.02 yd³ or 14 bags at 2 ft³ each.
Can I change the 10% settling allowance?
Yes. Waste / settling is a normal input. Increase it for fluffy bark that will compress, or lower it for a thin refresh on top of existing mulch.
Why does wet mulch weigh more?
Rain-soaked bark holds water. Density options in the list reflect dry reference values; weigh at the yard if you buy by the ton after a storm.
Which mulch density should I pick?
Hardwood mulch near 20 lb/ft³ is the default. Pine bark is lighter in the material list—switch if that matches your supplier label.
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By Home Yard Calc Editorial Team · Sources listed on the methodology page · Last updated October 26, 2026
Estimates only. Densities, coverage and salt targets vary by product, moisture and manufacturer. Confirm with your supplier or equipment manual. Not a substitute for professional design, soil engineering or pool service.