acalculator

How many cubic feet is it?

Enter the length, width and height of a box, or the diameter and height of a cylinder, in any unit. See the volume in cubic feet and in other units.

Your numbers

Units
Shape
Volume
24 ft³

The volume is 24 ft³.

Cubic inches
41,472 in³
Cubic yards
0.889 yd³
Cubic metres
0.6796 m³
US gallons
179.53 gal
Litres
679.6 L

Volume: 24 ft³. The volume is 24 ft³.

How to calculate

Computes the volume of a box or a cylinder, times how many, in cubic feet, with the same volume in cubic inches, cubic yards, cubic metres, US gallons and litres.

Example with the default inputs (Shape Box, Length 4 ft, Width 3 ft, Height 2 ft, How many 1): The volume is 24 ft³.

Method: box: length × width × height; cylinder: π × diameter² ÷ 4 × height; × how many

  • Each size may be in any length unit, including feet and inches together; the volume uses 1 ft = 12 in = 0.3048 m exactly.
  • Gallons are US liquid gallons of 231 cubic inches.

Machine-readable copies: Markdown, JSON.

Worked examples

Each example is checked against the calculator on every build.

  1. Shape Box, Length 4 ft, Width 3 ft, Height 2 ft, How many 1 gives Volume 24 ft³.Source: hand calculation in content.mdx: 4 × 3 × 2 = 24 ft³ = 179.5 US gal
  2. Shape Box, Length 1.5 ft, Width 1 ft, Height 0.8333 ft, How many 5 gives Volume 6.25 ft³.Source: hand calculation in content.mdx: 18 × 12 × 10 = 2,160 in³ = 1.25 ft³; × 5 = 6.25 ft³
  3. Shape Cylinder, Diameter 2 ft, Height 3 ft, How many 1 gives Volume 9.425 ft³.Source: hand calculation in content.mdx: π × 2² ÷ 4 × 3 = 3π = 9.425 ft³

How it works

  • Box (rectangular prism): volume = length × width × height.
  • Cylinder: volume = π × diameter² ÷ 4 × height.
  • Total = volume of one shape × how many.

The same volume is shown in other units, all converted exactly:

  • 1 ft³ = 1,728 in³ (12³).
  • 1 yd³ = 27 ft³ (3³).
  • 1 ft³ = 0.028316846592 m³ (0.3048³).
  • 1 US gallon = 231 in³, so 1 ft³ = 1,728 ÷ 231 = 7.4805 gallons.
  • 1 litre = 0.001 m³, so 1 ft³ = 28.3168 litres.

Worked examples by hand

A box 4 ft × 3 ft × 2 ft. 4 × 3 × 2 = 24 ft³. That is 24 × 1,728 ÷ 231 = 179.5 US gallons, and 24 ÷ 27 = 0.889 yd³.

Five boxes, each 18 in × 12 in × 10 in. 18 × 12 × 10 = 2,160 in³ = 2,160 ÷ 1,728 = 1.25 ft³ each, so 6.25 ft³ for five.

A cylinder 2 ft across and 3 ft tall. π × 2² ÷ 4 × 3 = 3π = 9.425 ft³, or 70.5 US gallons.

Other questions people ask

How do I calculate cubic feet?

Multiply length × width × height, all in feet. A box 4 ft × 3 ft × 2 ft is 4 × 3 × 2 = 24 cubic feet.

How do I calculate cubic feet from inches?

Multiply the three sizes in inches and divide by 1,728, the number of cubic inches in a cubic foot (12 × 12 × 12). A box 18 × 12 × 10 in is 2,160 in³ ÷ 1,728 = 1.25 ft³.

How many gallons are in a cubic foot?

A US gallon is 231 cubic inches, so a cubic foot (1,728 in³) holds 1,728 ÷ 231 = 7.48 US gallons, or 28.32 litres.

How do I find the cubic feet of a cylinder?

Multiply π × diameter² ÷ 4 by the height. A drum 2 ft across and 3 ft tall is π × 4 ÷ 4 × 3 = 9.42 ft³.

How many cubic feet are in a cubic yard?

A yard is 3 feet, so a cubic yard is 3 × 3 × 3 = 27 cubic feet. Divide cubic feet by 27 to get cubic yards.

Can I mix feet and inches?

Yes. Type a size such as 4 ft 6 in, or pick ft + in in the unit list. Each size is converted before the multiplication.