Material calculator
Calculate mulch for one or multiple garden beds. Estimate cubic yards, 1.5, 2, and 3 ft³ bags, purchase quantities, cost, and coverage by depth using US, metric, or mixed units.
How much mulch do you need to order?
Volume, bags, coverage, and cost
Project inputs
Estimate
Suggested bulk order
2.1yd³
1.557 m³ required before order rounding
Quantities include the submitted 10% extra material. Leftover below comes only from rounding to a 0.1 yd³ bulk increment or whole bags.
| Purchase option | Quantity | Purchased volume | Leftover | Total cost |
|---|---|---|---|---|
| Bulk cubic yards | 2.1 yd³ | 56.7 ft³ | 1.7 ft³ | — |
| 1.5 ft³ bags | 36.67 estimated · 37 to buy | 55.5 ft³2.056 yd³ | 0.5 ft³ | — |
| 2 ft³ bags | 27.5 estimated · 28 to buy | 56 ft³2.074 yd³ | 1 ft³ | — |
| 3 ft³ bags | 18.33 estimated · 19 to buy | 57 ft³2.111 yd³ | 2 ft³ | — |
Required bulk volume is 1.852 yd³ before extra material and 2.037 yd³ with it. Check the volume printed on the product bag before purchasing.
Enter prices for at least two available options to compare modeled purchase costs. No price is modeled for 1.5 ft³ bags.
Coverage uses the calculated base mulch volume before extra material, so the submitted depth matches your measured project area.
| Depth | Area covered | Difference vs your area | Status |
|---|---|---|---|
| 1 in | 600 ft²55.74 m² | +400 ft² | Extra coverage |
| 2 in | 300 ft²27.87 m² | +100 ft² | Extra coverage |
| 3 inCurrent depth | 200 ft²18.58 m² | 0 ft² | Covers project |
| 4 in | 150 ft²13.94 m² | −50 ft² | Short |
The suggested 2.1 yd³ bulk order contains 56.7 ft³. At your submitted depth it covers 226.8 ft².
| Depth | Area covered | Difference vs your area | Status |
|---|---|---|---|
| 2 in | 340.2 ft²31.61 m² | +140.2 ft² | Extra coverage |
| 3 inCurrent depth | 226.8 ft²21.07 m² | +26.8 ft² | Extra coverage |
| 4 in | 170.1 ft²15.8 m² | −29.9 ft² | Short |
Rectangle: length × width. Circle: π × radius². Triangle: base × perpendicular height ÷ 2. Add all area quantities, multiply by the shared depth, then add 10% extra. Purchase quantities use the existing 0.1 yd³ bulk increment and whole-bag rounding. Leftover is purchased volume minus required volume, never the submitted extra allowance. Reverse coverage divides normalized volume by each depth.
Mulch planning basics
Mulch volume is area × depth. The calculator converts every submitted dimension and the shared depth to consistent units, totals the measured bed area, and uses that result as the single source for cubic feet, cubic yards, cubic meters, bags, and purchase rounding. The optional extra percentage is added before either whole-bag or 0.1 yd³ bulk rounding.
Coverage depends on depth: the same 1 yd³ spreads over more area at a shallow depth and less area at a deeper one. These values come from the calculator's shared volume and unit-conversion engine.
| Depth | Square feet | Square meters |
|---|---|---|
| 1 in | 324 ft² | 30.1 m² |
| 2 in | 162 ft² | 15.05 m² |
| 3 in | 108 ft² | 10.03 m² |
| 4 in | 81 ft² | 7.53 m² |
One cubic yard equals 27 ft³, so the exact number depends on the package label. Exact equivalents are shown here; a real purchase must round any fractional result up to a whole bag.
For field measurement and depth considerations, read the mulch calculation guide. For stone paths or landscape beds, use the calculator for gravel instead of applying mulch assumptions.
Method
Measure each dimension, convert them to compatible units, apply the shape formula, add an extra allowance, and then estimate bulk cubic yards and bags from the total volume.
Measure each bed as a rectangle, circle, or triangle. Add their areas, multiply by the shared depth, then add the selected extra percentage. The result is converted to cubic feet, cubic yards, and cubic meters.
Volume changes directly with depth: a 4-inch layer uses twice the mulch of a 2-inch layer over the same area. For a fixed volume, coverage changes inversely with depth. The result table compares 1, 2, 3, and 4 inches and marks the submitted depth.
The mulch bag calculator divides final cubic feet by each centralized package size. It shows the exact estimate and then rounds upward to a whole purchase quantity for 1.5, 2, and 3 ft³ bags.
A 3 ft³ bag covers 50% more volume than a 2 ft³ bag, but package count alone does not determine value. Enter each bag price to compare the actual whole-bag purchase totals for this project.
Bulk mulch is commonly quoted by the cubic yard. The calculator shows exact required cubic yards and a suggested order rounded upward to 0.1 yd³ without inventing a minimum delivery quantity.
Bulk and bagged options are rounded independently. The comparison uses the suggested bulk order, whole bags to buy, the prices you enter, and the optional bulk delivery fee; no option is assumed to be cheaper in advance.
Bulk material cost is cubic yards to order multiplied by price per yard. Bulk total then adds the optional fixed delivery fee. Bag costs multiply whole 2 ft³ or 3 ft³ bags by their corresponding entered prices.
Enter each garden bed as its own measured area, select its shape, and use quantity only for genuinely identical beds. The calculator sums up to six areas and applies one consistent depth and extra percentage.
Worked examples
These examples use the same calculation logic as the calculator and isolate geometry and depth by using 0% extra material.
One 10 × 20 ft rectangle · 3 in depth · 0% extra
One 20 × 4 ft rectangle · 2 in depth · 0% extra
One 10 ft diameter circle · 3 in depth · 0% extra
Two 10 × 4 ft rectangles plus one 8 ft round bed · 3 in depth · 0% extra
Common questions
Add the area of each bed, multiply the total area by mulch depth, and divide cubic feet by 27. This calculator also applies the entered extra percentage and shows both calculated cubic yards and a suggested bulk order rounded up to 0.1 yd³.
Bag count depends on your final required cubic feet and the volume printed on each bag. The calculator compares 1.5, 2, and 3 ft³ sizes, shows the exact division, and rounds each purchase quantity up to a whole bag.
Coverage depends on depth. Convert one cubic yard to 27 cubic feet, convert the chosen depth to feet, and divide volume by depth. Use the engine-calculated coverage table to compare 1, 2, 3, and 4 inches with your submitted project area.
One cubic yard is 27 cubic feet. Divide 27 by the labeled volume of one bag to get the exact equivalent; the page table calculates this for 1.5, 2, and 3 ft³ bags. An exact conversion is different from a purchase quantity, which must be a whole number of bags.
Multiply the number of bags by the cubic feet printed on each bag, then divide the resulting cubic feet by 27. For a purchase plan, use whole bags; for an exact mathematical conversion, keep the unrounded result.
Depth depends on the site, plant type, mulch product, and any material already in the bed. The 3-inch default is an editable planning input, not a recommendation for every project; use the depth appropriate for your plants and site.
Not always. Enter a price per cubic yard, prices for 2 ft³ and 3 ft³ bags, and an optional fixed delivery fee. The calculator compares the current purchase quantities and identifies the lowest entered total without assuming bulk is universally cheaper.
Yes. Add up to six areas, choose a shape and dimensions for each, and use one shared mulch depth and extra percentage. The calculator sums all entered beds before calculating volume, bags, and bulk quantity.
Yes. Select Circle for an area and enter its diameter. The calculator divides the diameter by two and uses π × radius² to calculate that bed's area.
It adds a planning buffer for uneven ground and small measurement differences. The calculator applies 0% to 30% to base volume before any bag or bulk-order rounding, so extra material and order rounding remain separate.
Bulk total includes the fixed delivery fee only when you enter one. Bag totals do not include it. Taxes, labor, spreading, bed preparation, supplier minimums, and other vendor-specific charges are not modeled.
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