Java Program to Convert Decimal to Hexadecimal

This java program converts decimal value to hexadecimal value. First, user has to enter a decimal number, then we have to convert decimal value to hexadecimal value and finally displayed on the screen.

Hexadecimal Numerals: Hexadecimal is a base-16 number system. It uses 16 symbols, the symbols 0–9 to represent values zero to nine, and A, B, C, D, E, F (or alternatively a, b, c, d, e, f) to represent values ten to fifteen.

We can convert decimal to hexadecimal by two ways:

- Using built-in method (toHexString() method of Integer class)

- Without using built-in method

Java Program to Convert Decimal to Hexadecimal Using toHexString() Method

import java.util.Scanner;
class DecToHex
{
    public static void main(String args[])
    {
      Scanner scan = new Scanner(System.in);
      System.out.print("Enter Decimal Number : ");
      int dec = scan.nextInt();
        
      System.out.println("\nConverting...\n");
      String hex = Integer.toHexString(dec);
      System.out.println("Equivalent Hexadecimal is "+hex);
    }
}

Output:

Enter Decimal Number : 59

Converting...

Equivalent Hexadecimal is 3b

Java Program to Convert Decimal to Hexadecimal without Using Built-in Method

import java.util.Scanner;
class DecToHex
{
   public static void main(String args[])
   {
     Scanner scan = new Scanner( System.in );
     System.out.print("Enter Decimal number : ");
     int dec = scan.nextInt();
     int rem;
     String disp=""; 

     // Digits in hexadecimal number system
     char hex[]={'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};
     System.out.println("\nConverting...\n");
     while(dec!=0)
     {
       rem = dec%16; 
       disp = hex[rem]+disp; 
       dec = dec/16;
     }
     System.out.println("Equivalent Hexadecimal is "+disp);
  }
}

Output:

Enter Decimal number : 61

Converting...

Equivalent Hexadecimal is 3D