What is a cylinder calculator?
A cylinder calculator computes the volume and surface area of a right circular cylinder from the radius and height. A cylinder has two parallel circular bases and a curved lateral surface connecting them. You enter the radius of the base and the height (the perpendicular distance between the two bases); the calculator gives you volume = πr²h and total surface area = 2πr(r + h). No sign-up or download is required; the tool runs in your browser and is useful for geometry, engineering, and any task involving cylindrical shapes.
Cylinders appear in pipes, cans, tanks, drums, and many containers. Knowing the volume helps with capacity and fluid storage; surface area helps with material, paint, or insulation. This free cylinder calculator gives you volume in cubic units and surface area in square units—meters, feet, inches—as long as you use the same unit for radius and height. The formulas apply to a right circular cylinder (axis perpendicular to the bases).
How to use this cylinder calculator
Enter the radius of the circular base and the height of the cylinder. Both must be positive numbers. The radius is the distance from the center of the base to its edge; the height is the perpendicular distance between the two bases. As soon as both values are valid, the results appear: volume in cubic units and surface area in square units. The formulas are shown under the inputs: volume = πr²h, surface area = 2πr(r + h). If you enter zero or a negative value, the calculator will ask you to enter positive dimensions. Use the same unit for radius and height; volume will be in cubic units and surface area in square units of that measure.
Cylinder volume formula
The volume of a cylinder is V = πr²h, where r is the radius of the base and h is the height. So the volume is the area of the circular base (πr²) times the height. For example, if the radius is 3 units and the height is 10 units, volume = π × 9 × 10 ≈ 282.74 cubic units. The formula is the same as for a prism: base area times height; here the base is a circle. The cylinder calculator applies this formula so you get an accurate volume without doing the arithmetic by hand. Volume is always in cubic units when radius and height are in the same linear unit.
Surface area of a cylinder
The total surface area of a cylinder is the sum of the areas of the two circular bases and the lateral (curved) surface. Each base has area πr², so the two bases contribute 2πr². The lateral surface is a rectangle when “unwrapped”: one side is the height h and the other is the circumference of the base 2πr, so lateral area = 2πrh. Total surface area = 2πr² + 2πrh = 2πr(r + h). For radius 3 and height 10, surface area = 2π × 3 × (3 + 10) = 6π × 13 ≈ 245.04 square units. Use surface area when you need to paint, wrap, or coat the cylinder. This calculator gives you the total surface area (bases plus lateral) from radius and height.
Radius, height, and diameter
The radius is half the diameter; if you measure the diameter d, use r = d/2. Many real-world specs (pipes, cans) use diameter, so divide by 2 before entering the radius. The height is the perpendicular distance between the two bases—not the slant or the length along the curved surface. For a right circular cylinder, the axis (line joining the centers of the two bases) is perpendicular to the bases and its length is the height. This calculator needs radius and height; from those it computes volume and surface area. If you only know diameter, convert to radius first.
Cylinder vs cone and sphere
A cone with the same radius and height as a cylinder has one-third the volume: V_cone = (1/3)πr²h while V_cylinder = πr²h. So a cylinder holds three times as much as a cone with the same base and height. A sphere with radius r has volume (4/3)πr³ and surface area 4πr²; a cylinder with radius r and height 2r (so it “contains” the sphere) has volume 2πr³ and surface area 6πr². This cylinder calculator focuses on the cylinder; enter radius and height to get volume and surface area. For cones or spheres, use their dedicated calculators.
Applications of cylinder calculations
Cylinder volume and surface area are used in many fields. In engineering, pipes, tanks, and pressure vessels are often cylindrical; volume determines capacity and surface area affects heat transfer or coating. In construction, columns and silos are cylindrical. In packaging, cans and drums are cylindrical. In education, the cylinder is a standard solid when studying volume and surface area. This cylinder calculator gives you quick, accurate results from radius and height. Always measure radius (or diameter/2) and height in the same units, and keep units consistent for volume (cubic) and surface area (square).
Summary
This cylinder calculator finds the volume and surface area of a right circular cylinder from the radius and height. Enter radius and height (positive numbers) and get volume = πr²h and surface area = 2πr(r + h) instantly. The tool is free, runs in the browser, and requires no account. Use it for homework, design, tanks, or any cylindrical shape. Remember: radius is half the diameter; height is the perpendicular distance between the bases. Keep units consistent for accurate results.