Java Program to Find the Perimeter of a Circle

In this article, we will understand how to find the perimeter of a circle. The circumference is the perimeter of a circle. It's the distance around a circle.

Circumference is given by the formula C = 2𝜋\pi r where, \pi𝜋 = 3.14 and r is the radius of the circle −

Below is a demonstration of the same −

Input

Suppose our input is −

Radius of the circle : 5

Output

The desired output would be −

Perimeter of Circle is: 31.428571428571427

Algorithm

Step 1 - START
Step 2 - Declare 2 double values namely my_radius and my_perimeter
Step 3 - Read the required values from the user/ define the values
Step 4 – Calculate the perimeter using the formula using the formula (2*22*7)/7 and store
the result.
Step 5- Display the result
Step 6- Stop

Example 1

Here, the input is being entered by the user based on a prompt. You can try this example live in ourcoding ground tool .

import java.util.Scanner;
public class PerimeterOfCircle{
   public static void main(String args[]){
      double my_radius, my_perimeter;
      System.out.println("Required packages have been imported");
      Scanner my_scanner = new Scanner(System.in);
      System.out.println("A reader object has been defined ");
      System.out.print("Enter the radius of the circle : ");
      my_radius = my_scanner.nextDouble();
      my_perimeter =(22*2*my_radius)/7 ;
      System.out.println("The perimeter of Circle is: " +my_perimeter);
   }
}

Output

Required packages have been imported
A reader object has been defined
Enter the radius of the circle : 5
The perimeter of Circle is: 31.428571428571427

Example 2

Here, the integer has been previously defined, and its value is accessed and displayed on the console.

public class PerimeterOfCircle{
   public static void main(String args[]){
      double my_radius, my_perimeter;
      my_radius = 5;
      System.out.println("The radius of the circle is defined as " +my_radius);
      my_perimeter =(22*2*my_radius)/7 ;
      System.out.println("The perimeter of Circle is: " +my_perimeter);
   }
}

Output

The radius of the circle is defined as 5.0
The perimeter of Circle is: 31.428571428571427