About Bcrypt

Use Bcrypt to Hash and verify passwords. The tool runs in your browser for fast results and keeps your data local.

How to Use

  1. 1. Add your input or data.
  2. 2. Adjust options if needed.
  3. 3. Review the result and copy it.

What is Bcrypt Password Hashing?

Bcrypt is a password hashing function designed specifically for securely storing passwords. Unlike fast cryptographic hash functions like SHA-256, bcrypt is intentionally slow to resist brute-force attacks. It incorporates a salt (random data) automatically to prevent rainbow table attacks and uses a cost factor (work factor or rounds) that determines how computationally expensive the hashing process is. As computing power increases, you can increase the cost factor to maintain security. Bcrypt produces a 60-character hash string that includes the algorithm version, cost factor, salt, and the actual hash, making it self-contained and easy to verify. It is widely used in web applications, authentication systems, and password managers.

Common Use Cases

Bcrypt is the industry standard for password storage in modern applications. Web developers use bcrypt to hash user passwords during registration and verify them during login without storing plaintext passwords. Authentication systems use bcrypt to protect credentials in databases, ensuring that even if the database is compromised, passwords remain secure. API services use bcrypt to hash API keys and tokens for secure storage. Password managers use bcrypt to protect master passwords and vault encryption keys. System administrators use bcrypt in Linux/Unix systems for /etc/shadow password storage. Security auditors recommend bcrypt for compliance with data protection regulations like GDPR and PCI-DSS.

  • Hashing user passwords during registration in web apps
  • Verifying login credentials without storing plaintext
  • Protecting database credentials from breaches
  • Securing API keys and authentication tokens
  • Password manager master password protection
  • Linux/Unix system password storage
  • Meeting GDPR and PCI-DSS compliance requirements

Best Practices & Tips

Use a cost factor (salt rounds) of at least 10-12 for modern applications—higher values increase security but slow down hashing. Test the hashing time on your production hardware and aim for 250-500ms per hash to balance security and user experience. Never store plaintext passwords or use fast hash functions like MD5 or SHA-1 for passwords. Always use bcrypt library functions rather than implementing your own—libraries handle salt generation and verification correctly. When verifying passwords, use constant-time comparison to prevent timing attacks. Increase the cost factor periodically as hardware improves—rehash passwords on user login with the new cost factor. Store the full bcrypt hash string (including version, cost, and salt) in your database.

  • Use cost factor of 10-12 for modern applications
  • Aim for 250-500ms hashing time on production hardware
  • Never store plaintext passwords or use MD5/SHA-1
  • Use established bcrypt libraries, not custom implementations
  • Use constant-time comparison when verifying passwords
  • Increase cost factor periodically as hardware improves
  • Store the complete bcrypt hash string in database
  • Rehash passwords on login with updated cost factor

Troubleshooting Common Issues

If bcrypt hashing is too slow, reduce the cost factor—but never go below 10 for production systems. If verification always fails, ensure you are comparing the plaintext password against the full bcrypt hash string, not just part of it. Different bcrypt implementations may have compatibility issues—stick to one library across your stack. If you see "invalid salt" errors, verify the hash string is complete and not truncated in your database (bcrypt hashes are 60 characters). Performance issues during high traffic can be mitigated by using asynchronous bcrypt functions to avoid blocking the event loop. If migrating from another hash algorithm, implement a gradual migration strategy that rehashes passwords on successful login.

  • Hashing too slow causing poor user experience
  • Verification always failing due to incomplete hash comparison
  • Compatibility issues between different bcrypt libraries
  • Invalid salt errors from truncated hash strings in database
  • Performance bottlenecks during high traffic periods
  • Migration challenges from MD5 or SHA-1 to bcrypt
  • Cost factor too low compromising security

Frequently Asked Questions

Is Bcrypt free to use?

Yes. Bcrypt is free and works directly in your browser.

Does Bcrypt upload my data?

No. Most processing happens locally. Any network requests are clearly indicated.

What formats does Bcrypt support?

Bcrypt supports the common formats described on the page. Convert uncommon formats before pasting.

How should I share results from Bcrypt?

Copy the output and review any sensitive data before sharing or publishing.