SHA-1 Hash Code Generator

This tool generates SHA-1 hash codes from the entered text.

Steps for using this tool:

1. Enter or paste your text in the first text box and click Generate SHA-1 Hash Code button.
2. The SHA-1 hash code for the entered text appears in the second box.

SHA-1 Cryptography

SHA-1 is otherwise called as Secure Hash Algorithm 1. SHA-1 calculates hash codes for texts or file streams and generates a 160 bit hash code. This hash code will be in 40 digit hexadecimal number. The length of this hexadecimal hash code will be the same even if the input is 2 character string or 10,000 character text or 1GB file. For example, the SHA1 hash code for www.mytecbits.com is 74424e213bf77268c0abccb832762241f89f579d.

SHA-1 was found vulnerable to attacks. So, nowadays high security applications are using SHA-2 hashing algorithm. Still SHA-1 is the most commonly used encryption algorithm. SHA-1 hashing is used for cryptography and data integrity verifications like data validation, file validation, etc...

Uses of SHA-1 Hashing Algorithm

1. The best example is to verify the file downloaded from internet. While downloading a file from internet there are possibility of the file corrupted due to internet disconnections ot the file got tampered with. To verify the authenticity of the downloaded file, the SHA-1 hash code of the downloaded file can be verified with the SHA-1 hash code generated from the source file. Thus any tampering or data loss can be identified.
2. Generating SHA-1 hash code for strings and texts will be useful for password encryption, validating the authenticity of email content, etc..
3. SHA-1 is used as cryptography algorithm for SSH, SSL,... protocols.

Major programming languages has inbuilt SHA-1 classes to generate and verify SHA-1 hash codes.

.Net

.Net has System.Security.Cryptography.SHA1 abstract class. This class has ComputeHash(Byte[]), ComputeHash(Stream) and ComputeHash(Byte[], Int32, Int32) methods which can be used to generate SHA-1 hash codes.

A simple .Net C# class method which takes a string as input and returns SHA-1 hash code.

// SHA-1 Hash Code Generator Method
public static string SHA1Generator(string strInput)
{
	SHA1 sha1 = new SHA1CryptoServiceProvider();

        //provide the string in byte format to the ComputeHash method. 
	//This method returns the SHA-1 hash code in byte array
	byte[] arrHash = sha1.ComputeHash(Encoding.UTF8.GetBytes(strInput));

        // use a Stringbuilder to append the bytes from the array to create a SHA-1 hash code string.
	StringBuilder sbHash = new StringBuilder();

        // Loop through byte array of the hashed code and format each byte as a hexadecimal code.
	for (int i = 0; i < arrHash.Length; i++)
	{
		sbHash.Append(arrHash[i].ToString("x2"));
	}

        // Return the hexadecimal SHA-1 hash code string.
	return sbHash.ToString();
}

Java

In Java you can use the MessageDigest abstract class to generate the SHA-1 hash code for a string

A simple java class method which takes a string as input and returns SHA-1 hash code.

import java.math.BigInteger;
import java.security.MessageDigest;
 
public class SHA1 {
    public static String GenerateHash(String input) {
        MessageDigest objSHA = MessageDigest.getInstance("SHA-1");
        byte[] bytSHA = objSHA.digest(input.getBytes());
        BigInteger intNumber = new BigInteger(1, bytSHA);
        String strHashCode = intNumber.toString(16);
		
        // pad with 0 if the hexa digits are less then 40.
        while (strHashCode.length() < 40) {
            strHashCode = "0" + strHashCode;
        }
        return strHashCode;
    }
}

PHP

PHP has sha1() function to calculate MD5 hash code.

<?php
$str = "Hello";
echo sha1($str);
?>

• SHA-1 in wikipedia.org
• SHA-1 in .Net
• SHA-1 in Java
• SHA-1 in PHP