Enter the length, width, and height into the calculator to determine the total surface area of a rectangular prism. This calculator can also evaluate any of the variables given the others are known.

Total Surface Area Of A Rectangular Prism Formula

The following formula is used to calculate the total surface area of a rectangular prism. 

SA = 2lw + 2lh + 2wh

Variables:

  • SA is the total surface area (square units)
  • l is the length of the prism (units)
  • w is the width of the prism (units)
  • h is the height of the prism (units)

To calculate the total surface area of a rectangular prism, multiply the length by the width, then multiply the result by 2. Add this to the product of the length and height multiplied by 2. Finally, add the product of the width and height multiplied by 2. The sum of these three products gives the total surface area of the rectangular prism.

What is a Total Surface Area Of A Rectangular Prism?

The total surface area of a rectangular prism is the sum of the areas of all six of its faces. It is calculated by adding the areas of the three pairs of congruent faces. The formula to calculate it is 2lw + 2lh + 2wh, where l is the length, w is the width, and h is the height of the prism. This gives the total area that the surface of the prism covers.

How to Calculate Total Surface Area Of A Rectangular Prism?

The following steps outline how to calculate the Total Surface Area of a Rectangular Prism.

  1. First, determine the length of the prism (l) in units.
  2. Next, determine the width of the prism (w) in units.
  3. Next, determine the height of the prism (h) in units.
  4. Next, use the formula SA = 2lw + 2lh + 2wh to calculate the total surface area.
  5. Finally, calculate the Total Surface Area of the Rectangular Prism.
  6. After inserting the values of l, w, and h into the formula and calculating the result, check your answer with a calculator.

Example Problem:

Use the following variables as an example problem to test your knowledge.

Length of the prism (l) = 5 units

Width of the prism (w) = 3 units

Height of the prism (h) = 4 units