Bcrypt Hash Generator & Verifier
Generate and verify bcrypt password hashes with adjustable cost factor using this free online tool. No sign-up required, runs entirely in your browser.
What Is Bcrypt Hashing?
Bcrypt is a password-hashing function designed by Niels Provos and David Mazières based on the Blowfish cipher. Unlike fast hash algorithms like SHA-256, bcrypt is intentionally slow and includes a configurable cost factor (work factor) that controls how computationally expensive it is to produce a hash. This makes brute-force attacks significantly harder. Bcrypt also automatically generates and embeds a random salt in each hash, so identical passwords produce different hash values. The output format ($2a$, $2b$, or $2y$ prefix) encodes the algorithm version, cost factor, salt, and hash in a single 60-character string.
How to Use This Bcrypt Hash Tool
- To generate a hash: enter a password, adjust the cost factor (10 is a good default), and click Generate.
- The bcrypt hash appears instantly — copy it for storage in your database.
- To verify: switch to the Verify tab, enter the original password and the stored hash.
- Click Verify to check if the password matches the hash.
Common Use Cases for Bcrypt
- Secure password storage — Hash user passwords with bcrypt before storing them in a database. The built-in salt and adjustable cost factor protect against rainbow table and brute-force attacks.
- Password migration testing — When migrating authentication systems, quickly verify that existing bcrypt hashes still match their original passwords.
- Cost factor benchmarking — Test different cost factors to find the right balance between security and login performance for your server hardware.
- Development and debugging — Generate sample bcrypt hashes for use in test fixtures, seed data, or API development without needing a running backend.