Bcrypt Hash Generator and Checker
Generate salted bcrypt hashes or verify a password against an existing bcrypt hash locally, with UTF-8 length and cost validation.
How to use Bcrypt Hash Generator and Checker
- Enter a test password or password you are authorized to process.
- Choose generation and a cost, or verification and an existing hash.
- Run locally and copy the hash or inspect the match result.
Salted password hashing is intentionally different
A fresh hash includes a random salt, so hashing the same password twice normally produces different strings. Verification uses the salt and cost embedded in the supplied hash. The tool uses the existing bcryptjs library asynchronously in the browser and does not contact an authentication service or attempt password guessing.
Reject silent truncation and runaway costs
Bcrypt handles only the first 72 UTF-8 bytes of a password. This tool rejects longer input instead of silently truncating it. Generation costs are limited to 4–12 for an interactive browser task, and verification rejects encoded costs above 14 to bound local work. Cost selection still needs benchmarking in the system where hashes will be used; this tool does not prescribe a production password-storage policy.
Example input
demo-password
Can a bcrypt hash be decoded into a password?
No. The checker compares a supplied candidate with the hash; it does not recover the original password.
Is input uploaded?
Processing takes place in your browser. This tool does not send your input or selected files to a conversion API.