Calculate the volume of a rectangular prism (box or cuboid) instantly with this free interactive 3D calculator. The formula is V = l × w × h, where l is length, w is width, and h is height. Enter your three dimensions in the panel and watch the 3D model reshape in real time — volume and surface area are computed as you type.

Use this tool for everyday calculations: find the volume of a room (for AC sizing or paint estimation), determine shipping box capacity, calculate aquarium water volume, estimate swimming pool capacity, or figure out how much concrete you need for a slab. For example, a box measuring 3 × 4 × 5 cm has a volume of 60 cm³.

Need help? The built-in AI chat assistant can explain the difference between rectangular prisms and cubes, help with unit conversions (cubic feet to gallons, cm³ to liters), or walk you through word problems step by step.

Volume of a Rectangular Prism Calculator