The Cuboid

The cuboid is also referred to as a rectangular prism.  If your student does not understand why a cube, is also a prism I highly recommend you go to our explanation.

To be comfortable calculating volume and surface area, your child should be comfortable with multiplication as well as addition.

Surface Area of a Cuboid

We know that a cuboid is made up of six rectangular faces. We also know that these six faces come in three pairs.

Looking at the image to the left we can see the:

area of the front face is:

b x h (bh) 

This is the same as the area of the back face so we multiply it by 2:


We can see the area of the side face is: l x h (lh)

This is the same as the other side of the cuboid so we multiply it by 2:


We can see the area of the bottom face is:

l x b (lb)

This is the same as the top face, so we multiply it by 2:


The surface area is the area of all the shapes making the three dimensional shape, so we must add all these areas together:

2lh + 2lb + 2bh Units Squared 

Volume of a Cuboid

Looking at this image, we can see that there are three individual measurements on a cuboid.




The volume is:

Length x Breadth x Height

or to abbreviate it further:

V = lbh Units Cubed 

I am sure you will find all the information and worksheets you need here, however if there is anything you cannot find please don't hesitate to contact me.

I love to hear from my readers, and with a little feedback and a few suggestions I can make this a great resource for parents, teachers and tutors alike.

Be sure to explore everything on this site starting at the home page.

Return from this page on the Cuboid to our other 3d Geometric Shapes or Return to our k6 geometric shapes home page to explore more great basic geometry.