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Volume Calculator and surface area
Choose a solid, enter its dimensions and get the volume in exact form like 90π, with surface area for the round and box-shaped solids.
Answer
Enter your numbers or pick an example — the answer and the steps appear here instantly.
What it calculates
Volume formulas and where they come from
Prisms and cylinders: base × height
Any solid with the same cross-section all the way through has V = (area of base) × height. Box: lwh. Cylinder: πr²h. Triangular prism: ½·b·t × length, where b and t are the triangle's base and height.
Pyramids and cones: one third
A pointed solid holds exactly one third of the prism or cylinder with the same base and height. Rectangular pyramid: ⅓lwh. Cone: ⅓πr²h.
Sphere
V = (4/3)πr³ and surface area 4πr². A sphere of radius 3 has volume 36π ≈ 113.10 and surface area 36π as well, a numerical coincidence that only happens at r = 3.
Cone surface area
First find the slant height ℓ = √(r² + h²). The surface is then πr² for the base plus πrℓ for the side; with r = 3 and h = 4, ℓ = 5 and the total is 9π + 15π = 24π.
How to find a volume here
Choose the solid
The form shows only the measurements that solid needs, such as radius and height for a cylinder.
Enter dimensions in one unit
Mixing centimeters and meters gives a meaningless answer, and the calculator does not convert units for you.
Calculate
Volume appears in your unit cubed and surface area in your unit squared, each with its formula in the outline.
Need the reasoning?
“Explain step by step” sends the problem to the AI Math Solver for a written walkthrough of the setup and the arithmetic.
Frequently asked questions
It uses whatever unit you entered, cubed for volume and squared for surface area. Enter 5 cm and you read cm³; there is no unit conversion built in.
The calculator gives volume only for those two solids. Their surface area needs extra measurements, like slant heights or all three triangle sides, that the form does not ask for.
Both describe the same volume. 90π is exact, while 282.74 is rounded and therefore shown with ≈; use whichever form your teacher asks for.
A hemisphere is half a sphere, so compute the sphere's volume and divide by two: radius 3 gives 36π ÷ 2 = 18π.
The volume and surface-area results are free and computed in your browser with no account. Only the AI walkthrough is metered: it is included in the Pro plans* (*fair use: up to 300 runs a day across the writing, study and code tools), costs 2 credits without a plan, and can be previewed for free while signed out.
Use it as a study aid and double-check it, since AI explanations can contain mistakes. The calculator's own formula outline is the reference, and your course's rules decide how AI help may be used.
Tools that pair with volume problems
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Exact π answers, decimals and surface area from a few measurements.
Calculate volume- Seven solids
- Surface area for five
- Exact and decimal forms