Bcrypt Password Generator & Verifier

What Is a Bcrypt Generator?

A bcrypt generator is a tool that converts a password into a one-way password hash using the bcrypt algorithm. Developers use bcrypt to create password hashes for authentication systems, test login implementations and understand how password hashing works.

Unlike ordinary data encryption, password hashing is not designed to be reversed. An application stores the resulting hash instead of storing the original password. When a user attempts to log in, the application checks the submitted password against the stored hash.

How to Generate a Bcrypt Hash Online

1. Enter the password you want to hash in the Bcrypt Generator field.
2. Select a bcrypt cost factor. The default setting on this tool is 12.
3. Click the Generate Bcrypt Hash button.
4. Wait for the hashing operation to finish.
5. Copy the resulting bcrypt hash and use it for development or testing.

What Is the Bcrypt Cost Factor?

The bcrypt cost factor determines the computational effort used during password hashing. It is an exponent: each increase of one cost level approximately doubles the computational work.

For example, cost 10 represents a work factor of 2¹⁰, while cost 12 represents 2¹². A higher cost makes password hashing more expensive for both legitimate applications and attackers attempting large numbers of guesses.

The appropriate setting depends on the hardware and performance requirements of the application. Test the selected cost on the actual server that will verify passwords. A browser-based generator can take longer than a native server implementation.

Understanding the Bcrypt Hash Format

A standard bcrypt hash is 60 characters long. It contains the algorithm version, cost factor, salt and resulting password digest.

The example above illustrates the general structure. The actual salt and digest are generated by the bcrypt algorithm and are not fixed values.

• Version: Identifies the bcrypt format, commonly represented by prefixes such as $2a$, $2b$ or $2y$.
• Cost: Indicates the computational work factor used to generate the hash.
• Salt: A randomly generated value incorporated into the password hashing process.
• Digest: The resulting bcrypt password-hash value.

Why Does Bcrypt Generate a Different Hash Each Time?

Bcrypt uses a randomly generated salt. Consequently, generating a hash for the same password more than once normally produces different results.

This is expected behavior. When checking a password, use a bcrypt verification function rather than generating another hash and comparing the two strings. The verification function reads the salt and cost information from the existing hash.

Bcrypt's 72-Byte Password Limit

Bcrypt implementations commonly support a maximum password input length of 72 bytes. This is a byte limit rather than a character limit.

UTF-8 characters can occupy different numbers of bytes. Therefore, a password containing accented characters or emoji may reach the 72-byte limit before it reaches 72 visible characters.

This tool checks the UTF-8 byte length before generating a hash and rejects inputs that exceed the supported limit. This avoids silently hashing only part of a longer password.

Bcrypt vs. SHA-256 for Password Storage

SHA-256 is a general-purpose cryptographic hash function. It is designed to be fast. That makes it useful for integrity checks and other cryptographic applications, but it is not an appropriate standalone password-storage algorithm.

Bcrypt is specifically designed for password hashing. Its configurable work factor makes each password verification more computationally expensive.

For new systems, consider Argon2id where available. Bcrypt remains useful for compatibility with existing applications and systems that already use bcrypt hashes.

Using Bcrypt in PHP

PHP provides native password-hashing functions. The following example creates a bcrypt hash using PHP's password_hash() function:

$password = 'example-password';

$hash = password_hash(
    $password,
    PASSWORD_BCRYPT,
    ['cost' => 12]
);

echo $hash;

To verify a password against a stored bcrypt hash, use password_verify():

$password = 'example-password';

$storedHash = '$2y$12$...';

if (password_verify($password, $storedHash)) {
    echo 'Password is valid';
} else {
    echo 'Invalid password';
}

PHP automatically generates a salt when using password_hash() without a manually supplied salt. The resulting hash contains the information needed for password verification.

Is This Online Bcrypt Generator Private?

This tool uses browser-based bcrypt processing. The password and hash are handled by JavaScript in the visitor's browser; the tool does not submit them to a PHP form or store them in a Permitir.net database.

The page loads the bcrypt.js library from a public content delivery network. As with any website that loads third-party JavaScript, users should not enter real production credentials or sensitive passwords into an online tool. For production password handling, use a trusted implementation in your own application or development environment.