Bcrypt Hash Generator & Verifier
Generate and verify Bcrypt hashes for passwords online.
Securely generate Bcrypt hashes with adjustable cost factors. Verify if a plaintext password matches an existing Bcrypt hash instantly.
What is Bcrypt?
Bcrypt is a password-hashing function designed by Niels Provos and David Mazières, based on the Blowfish cipher. It is one of the most popular choices for securing passwords in web applications because it is computationally expensive and incorporates a salt to protect against rainbow table attacks.
Key features of Bcrypt include:
- Adaptive: As computers get faster, you can increase the "work factor" (cost) to keep the hashing process slow and secure.
- Salting: It automatically handles salt generation and includes it in the final hash string.
- Resistance: It is specifically designed to be resistant to brute-force attacks and hardware acceleration (GPU/ASIC).
How to Use This Tool
Generate a Bcrypt Hash
- Enter Password: Type or paste the password you want to hash in the "Generator" tab.
- Adjust Salt Rounds: Use the slider to set the Work Factor. The default is 10, which is sufficient for most modern applications. Higher values increase security but take longer to process.
- Generate: Click the "Generate Bcrypt Hash" button.
- Copy: Copy the resulting hash (which usually starts with
$2a$,$2b$, or$2y$) for use in your database.
Verify a Password
- Go to Verifier Tab: Switch to the "Verifier" tab.
- Enter Password: Provide the plaintext password you want to test.
- Paste Hash: Paste the Bcrypt hash string you want to verify against.
- Verify: Click "Verify Password". The tool will tell you instantly if they match.
Why Use Bcrypt instead of SHA-256?
Standard cryptographic hashes like SHA-256 or MD5 are designed to be fast. While speed is good for file integrity, it is a weakness for password storage because an attacker can try billions of passwords per second.
Bcrypt, however, is designed to be deliberately slow. By making the process take 100ms or more per password, it makes brute-force attacks practically impossible.
Security & Privacy
All processing is performed locally in your browser. Your passwords and hashes are never sent to our servers. We use the bcryptjs library to ensure that everything stays private on your machine.
Frequently Asked Questions
What are "Salt Rounds"?
Salt rounds (or cost factor) determine how many times the hashing algorithm is executed. Each increment in the rounds doubles the time required to hash. A value of 10-12 is currently considered standard for most web applications.
Why does the hash change every time I click generate?
Bcrypt generates a new random salt every time you hash a password. Even if the password is the same, the output hash will be different. This prevents "Rainbow Table" attacks where attackers pre-compute hashes for common passwords.
Is Bcrypt still secure?
Yes, Bcrypt remains a highly recommended algorithm for password storage. While newer algorithms like Argon2 exist and offer even better protection against GPU-based attacks, Bcrypt is still widely supported and considered very secure when used with a proper cost factor.
Can I reverse a Bcrypt hash?
No. Hashing is a one-way function. You cannot turn a hash back into the original password. Verification is done by hashing the input password again and comparing it to the stored hash.