Bcrypt Hash Generator

bcrypt is a password-hashing function designed in 1999 by Niels Provos and David Mazières. Unlike SHA-256 or MD5, bcrypt is intentionally slow and includes a cost factor that controls how many iterations to run. This makes brute-force attacks computationally expensive. bcrypt also automatically salts every hash, preventing rainbow table attacks.

The cost factor (also called work factor) is a power of 2 that controls how many iterations bcrypt runs. Cost 12 means 2^12 = 4,096 iterations. Cost 13 means 8,192 iterations. Higher cost = slower hash = harder to crack. The default of 12 is currently recommended for most applications. As hardware gets faster, you should increase the cost factor over time.

A bcrypt hash looks like: $2b$12$<salt><hash>. The $2b$ is the algorithm version (2b is standard), 12 is the cost factor, the next 22 characters are a base64-encoded random salt, and the final 31 characters are the hashed output. The full hash is always 60 characters.

Yes — that's the beauty of bcrypt. The salt is embedded directly in the hash string. When verifying, bcrypt extracts the salt from the stored hash and re-hashes the candidate password with the same salt and cost factor. If the results match, the password is correct. You never need to store the salt separately.

bcrypt is still widely considered safe for password hashing. However, security researchers now recommend Argon2id (the 2015 Password Hashing Competition winner) for new applications, because Argon2 is more resistant to GPU-based attacks (due to memory-hardness). If you're starting a new project, prefer Argon2id. For existing bcrypt systems, continue using it — bcrypt is not broken.