The area of a square is a basic but important concept in geometry. It measures the space enclosed within the four equal-length sides of a square. Since all sides are equal, calculating its area is straightforward, making it easier than most other shapes. You’ll often see the area of a square in math problems related to measurement, real estate planning, architecture, engineering, and school-level math.
In simple terms, the area of a square is the total space or surface that lies within the boundaries of the square.
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Let’s look at what is the area of a square is in more detail.
A square is a 2D closed figure with four equal sides and four 90-degree angles. When we refer to what is the area of a square, we mean the amount of flat space that it covers. This is always expressed in square units like square centimeters (cm²), square meters (m²), square inches (in²), and so on.
So, what is the area of a square?
It is the number of square units that fit inside the boundaries of the square.
For example:
If one side of a square is 5 meters, the area of the square = 5 × 5 = 25 m². This means 25 squares of 1m × 1m can fit inside the square.
Understanding the area of a square helps us solve real-life problems, such as figuring out how much carpet is needed for a square room or how much land a square plot covers.
To calculate the area of a square, we use a simple formula. Because all sides are equal, we don’t need different values for length and width like we do for rectangles.
The area of square formula is:
Area = side × side
Or simply:
Area = side²
Where “side” represents the length of one side of the square.
So, if you know the side of the square, plug it into the area of square formula to get the answer instantly.
Example:
If the side of a square is 9 cm, then
Area = 9 × 9 = 81 cm².
The area of square formula is one of the easiest to remember and use.
If you're wondering how to find the area of a square, the first step is to determine whether you have the side length or the diagonal.
This is the most direct method. Use the area of square formula:
Area = side × side
or
Area = side²
Example:
Side = 6 meters
Area = 6 × 6 = 36 m².
This is the simplest answer to how to find the area of a square.
Sometimes you have the diagonal of the square, not the side. In those cases, use the method for finding the area with the diagonal.
Use the formula: Area = (1/2) × diagonal²
So, when someone asks how to find the area of a square and gives you the diagonal, this formula is perfect.
Example:
Diagonal = 10 cm
Area = (1/2) × 10² = 50 cm²
Both these techniques help answer how to find the area of a square depending on what is provided in the question.
Let’s explain the concept of area of square using diagonal in more depth.
Every square can be split into two right-angled triangles by its diagonal. According to the Pythagorean Theorem, in a right triangle:
Diagonal² = side² + side² = 2 × side²
Now rearrange the formula:
side² = (diagonal²)/2
But we know side² is the area of square, so:
Area of square using diagonal = (1/2) × diagonal²
This is especially helpful when the side of the square is not known but the diagonal is given.
Example:
If diagonal = 14 cm
Area = (1/2) × 14² = (1/2) × 196 = 98 cm²
So, when you are only given the diagonal, you can confidently use the area of square using diagonal formula.
Let’s take another closer look at the area of square with diagonal.
We already derived that:
Area = (1/2) × diagonal²
This method is very useful in fields like engineering or architecture where diagonal measurements are often used.
Example:
Diagonal = 12 m
Area = (1/2) × 12² = (1/2) × 144 = 72 m²
So, if someone asks you to calculate the area of square with diagonal, this is the formula to use.
This method makes it easy to work with square shapes in real-life scenarios when only the diagonal is measurable.
Example 1:
Question: A square has a side of 10 cm. What is the area of square?
Solution:
Area = side × side = 10 × 10 = 100 cm²
Answer: 100 cm²
Example 2:
Question: What is the area of a square if each side is 13 meters?
Solution:
Area = side² = 13 × 13 = 169 m²
Answer: 169 m²
Example 3
Question: A square has a diagonal of 14 cm. Find the area of square using diagonal.
Solution:
Area = (1/2) × diagonal² = (1/2) × 14² = (1/2) × 196 = 98 cm²
Answer: 98 cm²
Example 4
Question: Find the area of square with diagonal 20 m.
Solution:
Area = (1/2) × diagonal² = (1/2) × 20² = (1/2) × 400 = 200 m²
Answer: 200 m²
Example 5
Question: A square tile has a side of 25 cm. What is the area of square?
Solution:
Area = side × side = 25 × 25 = 625 cm²
Answer: 625 cm²
Interior Design
If you want to lay carpet in a square room, measure the side and use the area formula to find out how much carpet you’ll need.
Agriculture
Farmers often need to calculate how much land they can use. For a square plot, the area = side × side gives them accurate results.
Art and Drawing
Drawing a square frame or grid on a canvas uses the idea of what is the area of a square to understand space coverage.
Construction
Engineers use both the area formulas based on side and diagonal to calculate the materials needed.
Technology
In screen design, if the screen is square and only the diagonal is known, use the area with diagonal formula to determine the screen size in inches².
Given |
Use Formula |
Side length (a) |
Area = a × a = a² |
Diagonal (d) |
Area = (1/2) × d² |
What is area? |
It is the space inside the square |
The area of square is one of the most practical and easy-to-use formulas in geometry. Whether you're measuring land, designing art, or working with screens, understanding what is the area of a square is essential. Use the area of square formula when the side is known, and switch to the area of square using diagonal or area of square with diagonal method when only the diagonal is provided. With both formulas in your toolkit, you’ll be ready to solve any square area problem in school or real life.
Related Links
2D Shapes - Understand the different types of 2D shapes, their properties, and how they form the foundation of basic geometry.
Area of Trapezium - Learn how to calculate the area of a trapezium using formulas, with step-by-step examples and visual aids.
Area of a Triangle - Understand how to calculate the area of a triangle with easy methods.
Area and Perimeter - Learn how to find the area and perimeter of different shapes with examples.
Ans: The formula for the area of square is:
Area = side × side = s²
Ans: The area of a square with side 4 cm is:
Area = 4 × 4 = 16 cm²
Ans: If the side of a square is 's':
Area = s²
Perimeter = 4 × s
Ans: The area of a rectangle is:
Area = length × breadth = l × b
Ans: A cube has 6 square faces. The surface area of a cube is:
Area = 6 × side²
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