What is a volume calculator?
A volume calculator computes the volume—the amount of three-dimensional space inside a solid—for various 3D shapes. Volume is always measured in cubic units: cubic meters, cubic feet, cubic inches, liters, gallons, and so on. This calculator supports five common solids: cube, rectangular prism, sphere, cylinder, and cone. You select a shape, enter the required dimensions (such as side length, length-width-height, or radius and height), and the tool gives you the volume and the formula used. No sign-up or download is required; it runs in your browser and is useful for homework, engineering, construction, and any task where you need to find volume quickly.
Understanding volume is essential in geometry and in many practical applications. Whether you are sizing a tank, ordering concrete for a slab, or comparing the capacity of different containers, a volume calculator saves time and reduces errors. This free volume calculator uses the same units you enter: if your dimensions are in meters, the result is in cubic meters; if in feet, the result is in cubic feet. Keep all measurements in one unit for consistent results.
How to use this volume calculator
First, choose the 3D shape from the dropdown: Cube, Rectangular Prism, Sphere, Cylinder, or Cone. The input fields update to match the shape. For a cube, enter the side length. For a rectangular prism, enter length, width, and height. For a sphere, enter the radius. For a cylinder or cone, enter radius and height. All values must be positive numbers. When the inputs are valid, click Get result to see the volume in cubic units and the formula used. The calculator displays the result and the formula so you can verify or learn the relationship. Change the shape or dimensions anytime and click Get result again for a new calculation.
Volume formulas by shape
Cube: Volume = side³. Multiply the side length by itself three times. Rectangular prism: Volume = length × width × height. The product of the three dimensions. Sphere: Volume = (4/3) × π × radius³, where π (pi) is approximately 3.14159. The radius is the distance from the center to the surface. Cylinder: Volume = π × radius² × height. The area of the circular base (πr²) times the height. Cone: Volume = (1/3) × π × radius² × height. A cone with the same base and height as a cylinder has one-third of the cylinder’s volume. This volume calculator applies the correct formula for the shape you select.
Understanding volume vs area and surface area
Volume measures the amount of 3D space inside a solid. It is different from area (the amount of 2D space inside a flat shape) and from surface area (the total area of the outer surface of a 3D shape). For example, a cube with side 2 has volume 8 cubic units, surface area 24 square units (six faces of area 4), and each face has area 4 square units. When you need to know how much a container holds, you use volume. When you need to know how much material covers the outside (paint, wrap), you use surface area. This calculator focuses on volume; for surface area, use a surface area calculator.
Common volume calculations and examples
Cube: A cube with side 3 meters has volume 3³ = 27 cubic meters. Rectangular prism: A box 5×4×3 feet has volume 60 cubic feet. Sphere: A sphere with radius 2 meters has volume (4/3)×π×8 ≈ 33.51 cubic meters. Cylinder: A cylinder with radius 3 cm and height 10 cm has volume π×9×10 ≈ 282.74 cubic cm. Cone: A cone with radius 4 units and height 6 units has volume (1/3)×π×16×6 ≈ 100.53 cubic units. You can enter these values in the calculator to verify and see the formulas in action.
Units and consistency
Volume is always in cubic units of whatever linear unit you use. If you enter dimensions in meters, the volume is in cubic meters (m³). If you enter in feet, the volume is in cubic feet (ft³). If you enter in inches, the volume is in cubic inches (in³). Never mix units in one calculation. For fluids, liters (L) and gallons (gal) are common; 1 cubic meter = 1000 liters, and conversion factors exist for gallons. Convert your dimensions to the desired unit before entering, or convert the result afterward using a volume converter.
Applications of volume calculations
Volume calculations are used in construction (concrete, backfill, tanks), manufacturing (container sizing, packaging), chemistry (reaction volumes, concentrations), engineering (pipes, reservoirs, fluid systems), shipping (cargo volume), and cooking (recipe scaling). Knowing the volume helps you order the right amount of material, compare container capacities, and plan projects. This volume calculator gives you instant results for five common 3D shapes so you can focus on measuring accurately and applying the numbers to your project.
Tips for accurate volume results
Measure dimensions with a ruler, tape measure, or calipers as appropriate. For cubes and rectangular prisms, measure length, width, and height along perpendicular edges. For spheres, cylinders, and cones, measure the radius (from center to edge) or measure the diameter and divide by 2; measure height perpendicular to the base. Ensure all values are in the same unit before clicking Get result. For irregular shapes, approximate with the nearest regular shape or use more advanced methods. The calculator does the math; accurate inputs give accurate volumes.
Summary
This volume calculator finds the volume of cubes, rectangular prisms, spheres, cylinders, and cones. Select a shape, enter the required dimensions in the same units, and click Get result to see the volume in cubic units and the formula used. The tool is free, runs in your browser, and requires no account. Use it for homework, engineering, construction, or any volume calculation. Keep units consistent and measure carefully for best results.