 Open in App
Not now

# Convert Hexadecimal value String to ASCII value String

• Difficulty Level : Hard
• Last Updated : 30 Mar, 2023

Given the Hexadecimal value string as input, the task is to convert the given hexadecimal value string into their corresponding ASCII format string.

Examples:

```Input: 6765656b73
Output: geeks

Input:  6176656e67657273
Output: avengers ```

The “Hexadecimal” or simply “Hex” numbering system uses the Base of 16 system. Being a Base-16 system, there are 16 possible digit symbols. Hexadecimal number uses 16 symbols {0, 1, 2, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F} to represent all numbers. Here, (A, B, C, D, E, F) represents (10, 11, 12, 13, 14, 15).

ASCII stands for American Standard Code for Information Interchange. ASCII is a standard that assigns letters, numbers, and other characters within the 256 slots available in the 8-bit code. E.g the lower case “h” character (Char) has a decimal value of 104, which is “01101000” in binary and “68” in hexadecimal.
For more ASCII values, refer to ASCII TABLE.

Algorithm:

1. Initialize final ascii string as empty.
2. Extract first two characters from the hexadecimal string taken as input.
3. Convert it into base 16 integer.
4. Cast this integer to character which is ASCII equivalent of 2 char hex.
5. Add this character to final string.
6. Extract next two characters from hexadecimal string and go to step 3. Implementation:

## C++

 `// C++ program to convert hexadecimal``// string to ASCII format string``#include ``using` `namespace` `std;` `string hexToASCII(string hex)``{``    ``// initialize the ASCII code string as empty.``    ``string ascii = ``""``;``    ``for` `(``size_t` `i = 0; i < hex.length(); i += 2)``    ``{``        ``// extract two characters from hex string``        ``string part = hex.substr(i, 2);` `        ``// change it into base 16 and``        ``// typecast as the character``        ``char` `ch = stoul(part, nullptr, 16);` `        ``// add this char to final ASCII string``        ``ascii += ch;``    ``}``    ``return` `ascii;``}` `// Driver Code``int` `main()``{``    ``// print the ASCII string.``    ``cout << hexToASCII(``"6765656b73"``) << endl;` `    ``return` `0;``}` `// This code is contributed by``// sanjeev2552`

## Java

 `// Java program to convert hexadecimal``// string to ASCII format string``import` `java.util.Scanner;` `public` `class` `HexadecimalToASCII {` `    ``public` `static` `String hexToASCII(String hex)``    ``{``        ``// initialize the ASCII code string as empty.``        ``String ascii = ``""``;` `        ``for` `(``int` `i = ``0``; i < hex.length(); i += ``2``) {` `            ``// extract two characters from hex string``            ``String part = hex.substring(i, i + ``2``);` `            ``// change it into base 16 and typecast as the character``            ``char` `ch = (``char``)Integer.parseInt(part, ``16``);` `            ``// add this char to final ASCII string``            ``ascii = ascii + ch;``        ``}` `        ``return` `ascii;``    ``}``    ``public` `static` `void` `main(String[] args)``    ``{``        ``// print the ASCII string.``        ``System.out.println(hexToASCII(``"6765656b73"``));``    ``}``}`

## Python3

 `# Python3 program to convert hexadecimal``# string to ASCII format string` `def` `hexToASCII(hexx):` `    ``# initialize the ASCII code string as empty.``    ``ascii ``=` `""` `    ``for` `i ``in` `range``(``0``, ``len``(hexx), ``2``):` `        ``# extract two characters from hex string``        ``part ``=` `hexx[i : i ``+` `2``]` `        ``# change it into base 16 and``        ``# typecast as the character``        ``ch ``=` `chr``(``int``(part, ``16``))` `        ``# add this char to final ASCII string``        ``ascii ``+``=` `ch``    ` `    ``return` `ascii` `# Driver Code``if` `__name__ ``=``=` `"__main__"``:` `    ``# print the ASCII string.``    ``print``(hexToASCII(``"6765656b73"``))` `# This code is contributed by``# sanjeev2552`

## C#

 `// C# program to convert hexadecimal``// string to ASCII format string``using` `System;` `class` `GFG``{``    ``public` `static` `String hexToASCII(String hex)``    ``{``        ``// initialize the ASCII code string as empty.``        ``String ascii = ``""``;` `        ``for` `(``int` `i = 0; i < hex.Length; i += 2)``        ``{` `            ``// extract two characters from hex string``            ``String part = hex.Substring(i, 2);` `            ``// change it into base 16 and``            ``// typecast as the character``            ``char` `ch = (``char``)Convert.ToInt32(part, 16);;` `            ``// add this char to final ASCII string``            ``ascii = ascii + ch;``        ``}``        ``return` `ascii;``    ``}``    ` `    ``// Driver Code``    ``public` `static` `void` `Main(String[] args)``    ``{``        ``// print the ASCII string.``        ``Console.WriteLine(hexToASCII(``"6765656b73"``));``    ``}``}` `// This code is contributed by PrinciRaj1992`

## Javascript

 ``

Output

`geeks`

Time complexity: O(N), where N is the length of the given string
Auxiliary space: O(N)

Approach 2: Using Bitwise Operations:

This approach is to use bitwise operations to directly convert the hexadecimal string to an ASCII string. In this approach, we would start by converting the hexadecimal string to a series of bytes. We can do this by iterating through the string and converting each pair of hexadecimal digits to a byte. Once we have the bytes, we can use bitwise operations to convert them to characters in the ASCII string.

In this implementation, we use a stringstream to build the ASCII string. We iterate through the hexadecimal string, converting each pair of hexadecimal digits to a byte using stoi. Then, we append the byte to the stringstream. Finally, we return the contents of the stringstream as the ASCII string.

Here is the code of this approach:

## C++

 `#include ``using` `namespace` `std;` `string hexToASCII(std::string hex) {``   ``stringstream ss;``    ``for` `(``size_t` `i = 0; i < hex.length(); i += 2) {``        ``unsigned ``char` `byte =stoi(hex.substr(i, 2), nullptr, 16);``        ``ss << byte;``    ``}``    ``return` `ss.str();``}` `int` `main() {``    ``string hexString = ``"6765656b73"``;``    ``string asciiString = hexToASCII(hexString);``    ``cout << asciiString << endl;``    ``return` `0;``}`

## Python3

 `def` `hex_to_ascii(hex_str):``    ``ascii_str ``=` `""``    ``for` `i ``in` `range``(``0``, ``len``(hex_str), ``2``):``        ``byte ``=` `int``(hex_str[i:i``+``2``], ``16``)``        ``ascii_str ``+``=` `chr``(byte)``    ``return` `ascii_str` `# Driver code``hex_string ``=` `"6765656b73"``ascii_string ``=` `hex_to_ascii(hex_string)``print``(ascii_string)`

Output

`geeks`

Time complexity: O(n), where N is the length of the given string
Auxiliary space: O(n)

My Personal Notes arrow_drop_up