How it works
Texas A&M AgriLife Extension (Travis County) gives “Total cubic yards = (Length feet × Width feet × (Depth inches / 12)) / 27” and the shortcut “Area … × Depth … × .0031”. The calculator uses the exact formula.
Bags = cubic feet ÷ the bag's cubic feet, rounded up. Weight uses the site's typical range of 0.2–0.4 tons per cubic yard.
Worked example
A 10 × 10 ft bed 3 in deep: 10 × 10 × (3 ÷ 12) = 25 cu ft, which is 0.93 cu yd or 13 bags of 2 cu ft. It weighs about 370–741 lb.
Tips and common mistakes
- Measure each bed separately and add them.
- Bag sizes vary; check the cubic feet printed on the bag.
Questions about this calculator
How many cubic feet are in a yard of mulch?
27 cubic feet.
How many cubic yards in a bag of mulch?
A 2 cu ft bag is 0.074 cu yd. 14 bags (13.5, rounded up) make a cubic yard.
How much mulch do I need for 100 square feet?
At 3 in deep: 25 cu ft, which is 0.93 cu yd or 13 bags of 2 cu ft.
Sources
Densities are a typical range — ask your supplier. Weight varies with moisture and gradation.
Values marked with a link come from the linked source, which opens in a new tab. Unit conversions and our own defaults are listed separately. Every value the site uses is in the methodology source register.
Where the numbers come from 5
- Common mulch bag sizes
- 0.75, 1, 1.25, 2 cu ft/bag
- Common sizes — check your bag. Texas A&M AgriLife Extension, Travis County, “How Much Compost, Soil or Mulch?” lists 0.75, 1, 1.25 and 2 cu ft bags (opens in a new tab)travis-tx.tamu.edu
- Mulch density range
- 0.2 – 0.4 US tons/cu yd
- Typical range; no primary standard exists, and weight varies with moisture and gradation. Confirm with your supplier.
- Meters per international foot
- 0.3048 m/ft
- NIST, international foot conversion (opens in a new tab)nist.gov
- Pounds per US short ton
- 2000 lb/US ton
- NIST Guide to the SI, US short ton (2000 lb) (opens in a new tab)nist.gov
- Kilograms per pound
- 0.45359237 kg/lb
- NIST Guide to the SI, pound conversion; exact definition (opens in a new tab)nist.gov
Unit conversions and our defaults11
- Inches per foot
- 12 in/ft
- Unit definition: one foot contains twelve inches
- Cubic feet per cubic yard
- 27 cu ft/cu yd
- Geometry: 3 × 3 × 3 feet
- Centimeters per meter
- 100 cm/m
- Metric prefix definition: centi is one hundredth
- Liters per cubic meter
- 1000 L/m³
- Metric definition: one liter is one cubic decimeter
- Circle constant π
- ≈ 3.14159 unitless
- Circle geometry, as specified in the owner brief
- Mulch calculator starting bag size
- 2 cu ft/bag
- Wave 2 pack default; editable selection
- Mulch calculator starting bed
- 10, 10, 3 ft length, ft width, in depth
- Wave 2 pack worked example; editable starting measurements
- Mulch depth unit-check threshold
- 12 in
- Owner specified unit-check warning, not a recommended depth
- Mulch, paver and sand circle starting diameter
- 10 ft
- Build choice: matches the starting length; editable, not a recommended size
- Count rounding tolerance
- 1e-9 unitless
- Owner specification: ceil(x − 1e-9)
- Volume and weight display precision
- 2 decimal places
- Owner specification: display volume and tons to two decimals