Security Tools/Bcrypt Hash Generator
Bcrypt Hash Generator
Hash and verify passwords with bcrypt algorithm
Generate Hash
Verify Password
Bcrypt Hash Guide
Learn about secure password hashing with bcrypt
What is Bcrypt?
Bcrypt is a password hashing function designed to be slow and computationally expensive, making it resistant to brute-force attacks. It automatically handles salting (adding random data) and allows adjustable work factors (cost rounds) to increase security over time as hardware improves.
How to Use
- Enter the password you want to hash
- Adjust the cost rounds (higher = more secure but slower)
- Click 'Generate Hash' to create the bcrypt hash
- To verify, enter both the password and hash, then click 'Verify'
Best Practices
- Use cost rounds of 10-12 for a good balance of security and performance
- Never store plain passwords - always hash them with bcrypt
- Increase cost rounds periodically as hardware becomes faster
Security Note
Bcrypt is the recommended algorithm for password hashing. Each hash includes a unique salt, so the same password will produce different hashes. The cost factor makes bcrypt resistant to GPU-based attacks, unlike SHA or MD5.
Frequently Asked Questions
Why is bcrypt better than SHA for passwords?
Bcrypt is intentionally slow (configurable via cost factor), making brute-force attacks impractical. It automatically generates and stores a unique salt with each hash, preventing rainbow table attacks. SHA is fast (bad for passwords) and requires manual salting. Bcrypt is purpose-built for password security.
What cost factor (rounds) should I use?
Use a cost that makes hashing take ~250ms on your server. In 2024, this is typically 10-12. Higher values (12-14) provide more security but increase login time and server load. Test on your production hardware. Increase cost every few years as hardware speeds up - you can rehash passwords on successful logins.
Why does bcrypt produce different hashes for the same password?
Bcrypt automatically generates a random 128-bit salt for each hash, which is stored within the hash string itself. This means the same password produces different hashes each time. The salt prevents attackers from using precomputed rainbow tables. Verification works because the salt is extracted from the stored hash.
What does the bcrypt hash format mean?
A bcrypt hash like '$2b$10$...' contains: $2b (algorithm version), $10 (cost factor = 2^10 iterations), followed by 22 characters of salt and 31 characters of hash. The entire string must be stored - you need both salt and cost factor for verification. Never truncate bcrypt hashes.
Should I also encrypt bcrypt hashes in my database?
Bcrypt hashes are designed to be safe even if exposed - that's their purpose. However, encrypting them adds defense in depth. If your encryption key is compromised alongside the database, you're back to just bcrypt protection. It's a reasonable extra layer but bcrypt alone is sufficient for most applications.