Password Strength Test
Estimate how long a password would survive an offline attack.
Hashing & encryption Client-side Entropy estimate + dictionary
Tool preview
How to use it
- 01
Type a password.
- 02
Read the entropy and crack-time estimate.
Limitations
- ! The estimate assumes a fast offline attacker and a random password; human-chosen passwords are weaker than the number suggests.
- ! Nothing is checked against breach databases.
FAQ
What does entropy in bits mean?
It is the base-2 logarithm of the number of guesses needed; each extra bit doubles the search space.
Is the password sent anywhere?
No. It is evaluated in the page.
Why does a long but simple password score well?
Length dominates in the entropy model; use the weak-password checker to catch dictionary patterns.
Files never leave your device
Processing happens in your browser using the File API, WebAssembly and Web Workers. There is no upload endpoint.
Technical details
- Processing
- Client-side
- Implementation
- Entropy estimate + dictionary
- Category
- Hashing & encryption
- Network requests
- None while processing