Password Strength Checker
The Password Strength Checker rates any password in real time, estimating its entropy and how long it would take to crack, so you know if it is truly secure.
Strength, measured properly
Rather than just counting character types, the checker estimates entropy - the mathematical unpredictability of your password - and converts it into an estimated crack time against modern hardware. Length matters most: a long passphrase beats a short string of random symbols.
To create strong passwords in the first place, use the Password Generator.
Frequently Asked Questions
What makes a password strong?
Length and unpredictability. A long passphrase of several random words is stronger and easier to remember than a short complex string.
Is my password sent anywhere when I test it?
No. The analysis runs entirely in your browser. As good practice, though, test similar patterns rather than your real active passwords.
What is password entropy?
It is a measure of how unpredictable a password is, in bits. Higher entropy means exponentially more combinations to guess.
How long should a password be?
Aim for at least 12-16 characters, or a passphrase of several random words, and use a unique one per account.
Related Security Tools
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