Mulch math is volume: area × depth, converted to cubic yards (the unit bulk delivery is sold in). Standard depth is 3 inches — enough to hold moisture and block weeds without suffocating roots. Refresh beds every spring with about half that on top.
Bags make sense under ~3 cubic yards; beyond that, bulk delivery by the yard is cheaper and easier on your back. The calculator shows both so you can price the job either way — and bill materials with a markup, not at cost.
Keep going with these tools — they build on this calculation: Lawn Mowing Price Calculator, Lawn Care Estimate Generator and Contractor Hourly Rate Calculator. When your prices look right, print the menu with the Menu Maker — free templates, PDF & PNG. Want us to set the whole system up for you? Ask about concierge setup.
Three inches on bare soil, two on refresh. More than four inches suffocates roots and invites fungus — "mulch volcanoes" against tree trunks are the classic mistake.
Thirteen to fourteen 2-cu-ft bags, or nine 3-cu-ft bags. Bulk delivery by the cubic yard almost always wins on price past three yards.