About bcrypt
Bcrypt is a password-hashing function designed to be deliberately slow and salted, which makes stored passwords very hard to crack even if a database leaks. This tool hashes a password with a chosen cost (work factor) and can also verify a password against an existing bcrypt hash. Everything runs in your browser, so passwords are never sent anywhere.
How Bcrypt works
How to use it
- Enter a password and pick a cost (10 is a good default).
- Click Hash to generate the salted bcrypt hash.
- To verify, paste a hash and a password and click Check.
What the cost means
The cost (or rounds) sets how much work the hash takes — each step up roughly doubles the time. Higher is more secure but slower; 10–12 suits most web apps.
Salting and verifying
Bcrypt builds a random salt into every hash, so the same password produces a different hash each time. Verification re-hashes the password with the stored salt and compares — which is why two different hashes can both be correct.
Common uses
- Hash a password for storage
- Verify a password against a bcrypt hash
- Generate test hashes for development
- Choose a safe work factor
- Check a login implementation
- Create seed users for a database
- Learn how bcrypt works
- Compare password hashing options