Free volume calculator for cubes, boxes, cylinders, spheres and cones. Get instant results in cm³, liters, gallons, cubic feet and cubic inches. Select a shape.
Volume is how much space a three-dimensional object takes up — and the right formula depends on the shape. A cylinder needs its radius and height, a box needs three measurements, a sphere only its radius.
This volume calculator covers the five most common shapes: cube, rectangular box, cylinder, sphere and cone. It shows the volume in cubic centimeters and converts it to liters, gallons, cubic feet and cubic inches at the same time.
Aquarium owners can size a tank, cooks check containers, DIYers estimate concrete or fill material, and students verify geometry homework — all without converting units by hand.
Select a shape and enter the dimensions shown; the volume and every conversion update instantly. Try the box with 30 × 20 × 10 cm to see 6 liters.
V = π r² h. For a radius of 5 cm and height of 20 cm: V = π × 25 × 20 ≈ 1,570.8 cm³ ≈ 1.57 L.
1 US gallon = 3.785 liters = 231 in³. Divide liters by 3.785 (or cm³ by 3785) — the calculator does it automatically.
V = 4/3 π r³: cube the radius, multiply by π, then by 4/3. A sphere of radius 5 cm has about 523.6 cm³.
Enter the tank's inner length, width and height in cm (box shape): cm³ ÷ 1000 = liters, ÷ 3785 = US gallons. Measure inside the glass, not outside.