Password Strength Checker
Developer ToolsEstimate password strength, entropy, and crack time.
- Entropy
- bits
- Guesses
- Time to crack
What is Password Strength Checker?
Password Strength Checker estimates how strong a password is using entropy and common attack models.
How to use Password Strength Checker
- 1 Type a password.
- 2 Read the strength estimate and crack-time.
- 3 Improve it based on the feedback.
Supported formats and limits
- Input: a password to test
- Output: strength, entropy and crack-time estimate
- Runs in your browser
Common uses
- Check whether a password is strong enough.
- Compare the strength of different passwords.
- Learn which patterns weaken a password.
Things to know
- Estimates are guidance, not a guarantee of security.
- Test in your browser; never enter a password you do not own.
Privacy and file handling
Passwords are analysed in your browser and never transmitted.
Frequently asked questions
Is it safe to type my real password?
The check runs entirely in your browser, but as a general habit avoid entering real passwords into any online form.
Is my password sent anywhere when I check its strength?
No. The check runs in your browser, so your password never leaves your device.
What makes a password strong?
Length, unpredictability and a mix of character types. Longer passphrases generally beat short, complex strings.
Does this tool store the password I type?
No. Nothing is stored or transmitted.
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