Volume Calculator
Calculate the volume of a cylinder, box, sphere or cone.
How to use this calculator
Pick a shape from the menu and the right input boxes appear — radius and height for a cylinder, length, width and height for a box, and so on. Enter the dimensions in any unit you like (centimetres, inches, metres) and press Calculate volume. The answer comes out in the cube of whatever unit you used, so metres in gives cubic metres out. The formula used is shown with your numbers so you can follow the working, which makes the tool useful for both quick estimates and checking maths homework.
The formulas explained
Each shape has its own volume formula:
Cylinder V = π r² h · Box V = l w h · Sphere V = 4⁄3 π r³ · Cone V = ⅓ π r² h
A cylinder is a circle of area π r² extended through a height h. A box is simply its three sides multiplied. A sphere's volume grows with the cube of its radius, which is why doubling a ball's radius makes it eight times bigger. A cone holds exactly one third of the cylinder that would enclose it, hence the ⅓ in its formula. Using consistent units for every dimension keeps the result correct.
A worked example
For a cylinder with radius 3 and height 10: the volume is π × 3² × 10 = π × 9 × 10 ≈ 282.74 cubic units. If those measurements were in centimetres, the tank holds about 282.74 cubic centimetres. Switch the shape menu to a sphere of radius 3 and the same calculator returns 4⁄3 × π × 27 ≈ 113.10 cubic units instead.
Frequently asked questions
How do you find the volume of a cylinder?
Multiply pi by the radius squared by the height: V = π r² h.
What is the volume of a box?
Length times width times height.
How do you find the volume of a sphere?
Four-thirds times pi times the radius cubed.