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Rectangular Prism Volume Calculator.

Calculate the volume of a rectangular prism.

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Set your values

Results update as you type.

02 / ANSWER

Length

Width

Height

Length must be finite.

Results update automatically as you type.

Use Cases

Packing and Shipping

Determine the volume of a box to estimate shipping costs or ensure it fits in a container.

Example: A box with dimensions 10 in × 8 in × 6 in has a volume of 480 cubic inches.

Construction and DIY

Calculate the volume of concrete or fill needed for a rectangular space.

Example: A slab 5 ft × 4 ft × 0.5 ft requires 10 cubic feet of concrete.

Frequently Asked Questions

How do I calculate the volume of a rectangular prism?: Multiply the length, width, and height of the prism together. The result is the volume in cubic units. For example, if length=5, width=3, and height=2, the volume is 5 × 3 × 2 = 30 cubic units.
What units should I use for length, width, and height?: You can use any unit of length (e.g., inches, feet, centimeters, meters) as long as all three dimensions are in the same unit. The volume will be in that unit cubed (e.g., cubic inches, cubic feet).
Can I use this calculator for a cube?: Yes, a cube is a special rectangular prism where all sides are equal. Simply enter the same value for length, width, and height.

Tips & Common Mistakes

Tips

Ensure all dimensions are in the same unit before calculating to get an accurate volume.
For large numbers, double-check your entries to avoid errors.
If you need the volume in a different unit, convert the dimensions first or convert the result afterward.
Remember that volume is always expressed in cubic units, not square units.

Common Mistakes to Avoid

Using different units for length, width, and height without converting, leading to incorrect volume.
Forgetting to multiply all three dimensions, or only multiplying two.
Confusing volume with surface area, which is the sum of the areas of all faces.

Last updated: August 13, 2026

Use Cases

Packing and Shipping

Determine the volume of a box to estimate shipping costs or ensure it fits in a container.

Example: A box with dimensions 10 in × 8 in × 6 in has a volume of 480 cubic inches.

Construction and DIY

Calculate the volume of concrete or fill needed for a rectangular space.

Example: A slab 5 ft × 4 ft × 0.5 ft requires 10 cubic feet of concrete.

Frequently Asked Questions

How do I calculate the volume of a rectangular prism?

Multiply the length, width, and height of the prism together. The result is the volume in cubic units. For example, if length=5, width=3, and height=2, the volume is 5 × 3 × 2 = 30 cubic units.

What units should I use for length, width, and height?

You can use any unit of length (e.g., inches, feet, centimeters, meters) as long as all three dimensions are in the same unit. The volume will be in that unit cubed (e.g., cubic inches, cubic feet).

Can I use this calculator for a cube?

Yes, a cube is a special rectangular prism where all sides are equal. Simply enter the same value for length, width, and height.

Tips & Common Mistakes

Tips

Ensure all dimensions are in the same unit before calculating to get an accurate volume.
For large numbers, double-check your entries to avoid errors.
If you need the volume in a different unit, convert the dimensions first or convert the result afterward.
Remember that volume is always expressed in cubic units, not square units.

Common Mistakes to Avoid

Using different units for length, width, and height without converting, leading to incorrect volume.
Forgetting to multiply all three dimensions, or only multiplying two.
Confusing volume with surface area, which is the sum of the areas of all faces.

Use Cases

Packing and Shipping

Determine the volume of a box to estimate shipping costs or ensure it fits in a container.

Example: A box with dimensions 10 in × 8 in × 6 in has a volume of 480 cubic inches.

Construction and DIY

Calculate the volume of concrete or fill needed for a rectangular space.

Example: A slab 5 ft × 4 ft × 0.5 ft requires 10 cubic feet of concrete.

Frequently Asked Questions

How do I calculate the volume of a rectangular prism?

Multiply the length, width, and height of the prism together. The result is the volume in cubic units. For example, if length=5, width=3, and height=2, the volume is 5 × 3 × 2 = 30 cubic units.

What units should I use for length, width, and height?

You can use any unit of length (e.g., inches, feet, centimeters, meters) as long as all three dimensions are in the same unit. The volume will be in that unit cubed (e.g., cubic inches, cubic feet).

Can I use this calculator for a cube?

Yes, a cube is a special rectangular prism where all sides are equal. Simply enter the same value for length, width, and height.

Tips & Common Mistakes

Tips

Ensure all dimensions are in the same unit before calculating to get an accurate volume.
For large numbers, double-check your entries to avoid errors.
If you need the volume in a different unit, convert the dimensions first or convert the result afterward.
Remember that volume is always expressed in cubic units, not square units.

Common Mistakes to Avoid

Using different units for length, width, and height without converting, leading to incorrect volume.
Forgetting to multiply all three dimensions, or only multiplying two.
Confusing volume with surface area, which is the sum of the areas of all faces.