Rectangle Calculator

Use this online calculator to calculate the properties fo a rectangle

Note - changing area or volume affects height, width and depth. Tick the "lock" boxes to maintain the required dimensions (if all unlocked depth will be changed)

Dimensions for 2d rectangle
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Dimensions for 3d rectangle
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Rectangle Calculator. This image shows a 2D rectangle and a 3D rectangle with associated calculations used by the Rectangle Calculator

How to calculate the area of a Rectangle

a x b = c where:

  • a = width
  • b = height
  • c = area of a rectangle

How to calculate the area of a Rectangular Cuboid

a x b x c = d where:

  • a = width
  • b = height
  • c = depth area of a rectangle
  • d = area of a rectangular cuboid

Why Choose the Rectangle Calculator for Calculating 2D Shapes?

A rectangle calculator, as the name suggests, is used to find the area and the diagonal of a rectangle. A rectangle is a 2-dimensional geometric shape with equal and parallel opposite sides and all adjacent sides making a right angle at the corner.

We come across rectangles in our daily life more often than we observe. From a simple almirah to the refrigerator or a book that you read to the laptop screen, the face of all these items is rectangular in shape with varying measurements.

However, before we proceed towards understanding the rectangle calculator better, let's get familiar with the properties of a rectangle.

Properties of a Rectangle

A rectangle has the following properties:

  • All the interior angles are 90°.
  • The diagonals of a rectangle intersect at midpoint, i.e., they are bisectors of each other.
  • As mentioned earlier, the opposite sides of a rectangle are equal and parallel.
  • A rectangle with length 'a' and width/height 'b' has an area of a x b.
  • The perimeter of a rectangle is twice the sum of the sides, i.e., 2(a+b).
  • The length of the diagonal is the root of the sum of the square of both sides, i.e., √(a²+b²).
  • The length of both diagonals of a rectangle is equal.
  • The diagonal is equal to the length of the diameter of the circumcircle.

What is a 3-Dimensional Rectangle?

The shape formed by a 3-d rectangle also depends on how you project it. If you rotate a rectangle along its length or breadth, you will get a cylinder. However, if you extend the same rectangle to a depth 'd', it will become a cuboid.

However, in general terms, a cuboid is considered to be the truest form of 3-dimensional rectangle since a cylinder can also be developed by extending a circle along its plane to a certain length.

Using the Rectangle Calculator

The rectangle calculator developed by icalculator can be used for both the 2 dimensional and 3 dimensional rectangles.

In case of the 2-dimensional calculator, simply use the upper part of the calculator to type in the height and width of the rectangle. The calculator will automatically give you the area and the length of the diagonal.

To find volume and surface area of a 3-dimensional rectangle, all you need to do is repeat the steps mentioned above and enter the depth in the second calculator, placed right below the 2-d rectangle calculator. And there you have it, the complete rectangle calculation including the area of the 2-d rectangle and the volume and surface area of the 3-d rectangle.

In case of fractional values, you can also choose up to 9 decimal places for the calculations.

Use of the Rectangle Calculator in Daily Life

You come across rectangles throughout the day. The doors you open and close, the ice cream sandwich you so love to eat, the books you read so dearly, even the screen of your computer or phone that you are reading this article on, they all are rectangles.

Rectangle calculators are used in buildings to figure out the area of the floor, to calculate the area of a soccer field.

Carrying out calculations involving huge measurements becomes a tough job, especially when you need to do it multiple times a day, on a routine basis. This is where the rectangle calculator saves you time and effort. From the dimensions of a rectangular microchip to the area of a rectangular hangar, you can calculate it all. The same calculator also gives you the diagonal length so that you know where the center of the rectangle is.

Put simply, the rectangular calculator makes your life simple and easy, one length or breadth at a time.

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