Bcrypt Hash Generator & Verifier
Generate and verify cryptographically secure Bcrypt password hashes with configurable work factors and timing-safe matching.
At a glance
Bcrypt Hash Generator & Verifier is a free web tool that generates and verifies cryptographically secure Bcrypt password hashes in your browser. Full compatibility with modern standard $2b$, legacy $2a$, and PHP crypt $2y$ prefix revisions. Everything runs locally in your browser — nothing is uploaded and no sign-up is needed.
100% In-Browser Bcrypt Processing
All Eksblowfish key derivations and constant-time password comparisons execute in local browser memory. No credentials or hashes are ever sent to any server.
Awaiting Input
Enter a candidate password and an existing bcrypt hash above to verify constant-time match.
Work Factor Adaptability
Unlike fast cryptographic hashes (SHA-256 or MD5), bcrypt features a configurable work factor ($2^{\text{cost}}$). As hardware speeds increase, password security is scaled up by incrementing the rounds.
Timing Attack Protection
Password verification uses constant-time string comparison algorithms, preventing side-channel timing attacks that attempt to deduce hash checksum characters from CPU execution latency.
Automatic 128-Bit Salt
Every generated hash includes an automatically seeded 16-byte cryptographically secure random salt. This makes precomputed rainbow table attacks impossible.
Frequently Asked Questions
What is the difference between $2a$, $2b$, and $2y$ prefixes?
$2a$ is the original OpenBSD implementation specification. In 2011, PHP's crypt library fixed a UTF-8 character length bug using $2y$. In 2014, OpenBSD released $2b$ to resolve a wraparound bug with passwords longer than 255 bytes. $2b$ is the current industry standard.
Why is a cost factor of 10 recommended?
Cost factor 10 corresponds to $2^{10} = 1,024$ key expansion rounds, which takes approximately 60–100ms on modern CPUs. This offers an optimal balance between user authentication responsiveness and resistance to offline brute-force cracking.
Are passwords or hashes sent over the network?
No. The Eksblowfish algorithm runs completely in your web browser memory using client-side JavaScript. No passwords, hashes, or analytical telemetry ever leave your machine.
Why Use This Bcrypt Hash Generator & Verifier?
How to Use Bcrypt Hash Generator & Verifier
Enter Password or Generate Random
Type your plaintext password into the generator input or click Random Password for a high-entropy string.
Configure Cost & Prefix
Adjust the work factor slider (default 10) and choose your algorithm revision ($2b$, $2a$, or $2y$).
Copy Hash or Verify Match
Copy the generated 60-character bcrypt hash or switch to the Verify Password tab to test candidate passwords.
Worked example: Bcrypt Hash Generator & Verifier
Executed entirely inside your local browser memory using modern Web APIs. The engine verifies input syntax, performs deterministic transformation, and exposes instant copy or download options.
sample_payload.text (Valid format conforming to TEXT specification)
converted_result.hash (100% client-side)
Technical Specifications & Engine Details
| Specification | Details |
|---|---|
| Supported Formats | TEXT → HASH, TEXT |
| Execution Mode | 100% Client-Side In-Browser (client) |
| Browser Requirements | Requires modern web browser with Web Crypto API and standard DOM APIs. |
| Performance Constraints | Pure JavaScript client-side execution; recommended cost factors 4 to 14 for interactive browser performance. |
100% Client-Side Privacy Guarantee
All Eksblowfish key expansions, random salt generations, and bcrypt verifications run 100% locally in your browser memory. No data is ever transmitted to external servers.
Frequently Asked Questions
What is the difference between $2a$, $2b$, and $2y$ prefixes?
Why is Bcrypt preferred over SHA-256 for passwords?
Are passwords sent to any server?
What cost factor should I use in production?
Methodology
Rankings and recommendations here are never paid for.
Last updated .