Free Volume Calculator 2026 to calculate the volume of cubes, cylinders, cones and spheres in cubic meters, feet, liters and gallons. Fast and accurate 3D shape volume tool.
Calculate volume for various 3D shapes.
Cube: Side³
Rectangular Prism: Length × Width × Height
Cylinder: π × Radius² × Height
Sphere: (4/3) × π × Radius³
Cone: (1/3) × π × Radius² × Height
The calculator automatically converts between cubic feet, cubic meters, liters, gallons, and other common volume units.
For rectangular pools, multiply length × width × average depth. For circular pools, use the cylinder formula with radius and depth.
One cubic foot equals approximately 7.48 gallons. This is useful for calculating water tank capacities.
For irregular shapes, break them into regular shapes, calculate each volume, and add them together. Or use water displacement method for physical objects.