📏 Enter known values
Formula Reference
Worked example
If we use the result to calculate Height, we should get the value you entered:
How to calculate the volume of a rectangular prism
A rectangular prism (a box, or cuboid) has six rectangular faces. Its volume is the product of its three dimensions:
\[ V = \text{Length} \times \text{Width} \times \text{Height} \]
It is the area of the base (length × width) times the height. If you know the volume and two dimensions, divide to get the third one:
\[ \text{Height} = \frac{V}{\text{Length} \times \text{Width}} \]
How to use the calculator
- Enter three of the four values: the volume, the height, the length and the width.
- Leave empty the one you want to find.
- Press Calculate. Use the same unit for the three dimensions; the volume is in that unit cubed.
Worked examples
1. Box of 30 × 20 × 15 cm
\[ V = 30 \times 20 \times 15 = 9{,}000\ \text{cm}^3 = 9\ \text{L} \]
2. Fish tank
An aquarium 80 cm long, 35 cm wide and 40 cm tall holds \( 80 \times 35 \times 40 = 112{,}000\ \text{cm}^3 \), that is, 112 liters. Filled up to 35 cm, it holds 98 liters.
3. Concrete for a slab
A slab 5 m long, 4 m wide and 10 cm thick needs \( 5 \times 4 \times 0.1 = 2\ \text{m}^3 \) of concrete. Convert the thickness to meters before multiplying.
4. Height from the volume
A 60 L container (60,000 cm³) with a base of 50 × 30 cm is \( 60{,}000 \div (50 \times 30) = 40 \) cm tall.
Volume units
| Unit | Equivalent |
|---|---|
| 1 cm³ | 1 mL |
| 1 dm³ | 1 L = 1,000 cm³ |
| 1 m³ | 1,000 L = 1,000,000 cm³ |
| 1 ft³ | 28.32 L |
| 1 in³ | 16.39 mL |
Other measurements of a box
- Surface area: \( A = 2(LW + LH + WH) \).
- Space diagonal: \( d = \sqrt{L^2 + W^2 + H^2} \), the longest straight object that fits inside.
- A cube is a prism with three equal dimensions: \( V = a^3 \).
When Do You Need to Calculate the Volume of a Rectangular Prism?
Moving trucks, containers and couriers charge by volume. Measuring each box gives the space you need and the shipping cost.
Choose the right truck or package sizeThe volume of a fish tank or a water tank tells you how many liters it holds, how much conditioner to add and how heavy it will be: 1 liter of water weighs about 1 kg.
Water volume, dosing and weightSlabs, footings and trenches are rectangular prisms. Their volume gives the cubic meters of concrete to order or of earth to dig.
Order concrete without running shortHeating and air conditioning are sized by the volume of air in a room: length × width × ceiling height.
Choose a unit of the right powerRectangular beds and planters are filled with soil by volume. Their volume tells how many bags of soil to buy.
Buy the right amount of soilThe volume of a box is the starting point for units of volume, density and capacity at school.
Practice with cubic units and conversionsCommon Mistakes
⚠️ Adding Instead of Multiplying
⚠️ Mixed Units
⚠️ Confusing Volume and Surface
⚠️ Outside Instead of Inside Dimensions
⚠️ Wrong Liter Conversion
⚠️ Filling to the Brim
Applications by Industry
Logistics & Shipping
- Containers: Cargo volume in containers and trucks
- Couriers: Volumetric weight of packages
- Warehouses: Storage capacity of shelves and pallets
Construction
- Concrete: Volume of slabs, beams and footings
- Excavation: Earth removed from trenches and pits
- Materials: Volume of bricks and blocks
Heating & Air Conditioning
- Rooms: Air volume to size heating and cooling
- Ventilation: Air changes per hour
- Ducts: Volume of rectangular ducts
Aquariums & Water Storage
- Fish tanks: Liters of water and treatment doses
- Cisterns: Capacity of rectangular cisterns
- Pools: Water in rectangular pools with a flat bottom
Manufacturing & Packaging
- Boxes: Box sizes for products
- Molds: Material for rectangular molds
- Stock: Volume and weight of metal blocks
Education
- Geometry: Volume as base area × height
- Physics: Density = mass ÷ volume
- Units: Converting between cm³, liters and m³
External Resources
- Cuboids and rectangular prisms: volume and surface area — Math is Fun
- Cuboid definition and properties — Wikipedia