Cubic feet calculator
The cubic feet in a box, room, raised bed or tank, with cubic yards, gallons and how many bags of soil or mulch it takes.
Your volume adds up to
24.00 cubic feet
- Cubic yards
- 0.89 cu yd
- Gallons
- 179.5 gal
- Liters
- 679.6 L
- Cubic meters
- 0.68 m³
- Cubic inches
- 41,472 cu in
- Bags to buy
- bags
- Estimated cost
Gallons are US liquid gallons. Bags are rounded up to whole bags.
How to calculate cubic feet
Measure length, width and height in feet and multiply them. A cubic foot is a cube 1 foot on each side, so the answer counts how many of those cubes fit.
- Box or room = length × width × height
- Cylinder = 3.1416 × radius² × height (radius = diameter ÷ 2)
- Measured in inches? Multiply the inches, then divide by 1,728 (12 × 12 × 12).
- Cubic yards = cubic feet ÷ 27; gallons = cubic feet × 7.4805
Worked example
3 moving boxes, each 18 × 18 × 16 inches: 18 × 18 × 16 = 5,184 cubic inches, ÷ 1,728 = 3 cu ft each. 3 boxes × 3 = 9 cubic feet.
Convert cubic feet to gallons, yards and liters
Already know the volume? Convert between cubic feet, gallons, cubic yards, cubic inches, cubic meters, liters and quarts.
Cubic foot conversions and bag sizes
| Volume | Cubic feet | Gallons | Liters |
|---|---|---|---|
| 1 cubic foot | 1 | 7.4805 | 28.3168 |
| 1 cubic yard | 27 | 201.974 | 764.5549 |
| 1 gallon | 0.133681 | 1 | 3.7854 |
| 1 cubic meter | 35.3147 | 264.1721 | 1,000 |
Bags and buckets in cubic feet
Potting soil is often sold by the quart and mulch and garden soil by the cubic foot. Here is what common sizes hold, and how many it takes to make a cubic yard.
| Container | Cubic feet | Per cubic yard |
|---|---|---|
| 8-quart bag | 0.27 | 101.0 |
| 16-quart bag | 0.53 | 50.5 |
| 5-gallon bucket | 0.67 | 40.4 |
| 1 cu ft bag | 1.00 | 27.0 |
| 1.5 cu ft bag | 1.50 | 18.0 |
| 2 cu ft bag | 2.00 | 13.5 |
| 3 cu ft bag | 3.00 | 9.0 |
Cubic feet questions
How many cubic feet are in a cubic yard?
27. A cubic yard is 3 × 3 × 3 feet. Divide cubic feet by 27 to get cubic yards, which is how bulk soil, mulch, gravel and concrete are sold. For those, the cubic yard calculator works from square feet and depth.
How many gallons are in a cubic foot?
About 7.48 US gallons, or 28.3 liters. A US gallon is defined as 231 cubic inches, and a cubic foot is 1,728, so a cubic foot holds 1,728 ÷ 231 gallons.
How do I calculate cubic feet from inches?
Multiply length, width and height in inches, then divide by 1,728. A 18 × 18 × 16 in box is 5,184 ÷ 1,728 = 3 cubic feet. Choose "inches" above and the calculator does it for you.
How many cubic feet are in a 5-gallon bucket?
About 0.67 cubic feet if it's filled to the 5-gallon line, so it takes about 1.5 buckets to make a cubic foot and 40 to make a cubic yard. Many buckets hold a little more when filled to the rim.
How many bags of soil or mulch do I need?
Work out the cubic feet, then divide by the bag size and round up. An 8 × 4 ft raised bed 1 ft deep holds 32 cubic feet, which is 22 bags of 1.5 cu ft. Enter your bag size above. For beds and paths spread by depth, the mulch calculator works from square feet.
Can I convert cubic feet to square feet?
Only if you know the depth or height, because cubic feet measure volume and square feet measure area. Divide cubic feet by the height in feet: a 4 × 3 × 2 ft box is 24 cubic feet, and 24 ÷ 2 = 12 square feet of floor. For floor area on its own, use the square footage calculator.