Password Strength Checker
Check how strong a password is with an entropy estimate, common password and pattern detection, and an estimated offline cracking time.
Runs on your device
Result
Results appear here as you type.
What it does
Length matters more than complexity. The checker estimates entropy from length and character variety, then penalises common words, repeats, sequences and years.
How to use it
- Type a password you are considering.
- Read the strength, issues and crack time.
- Lengthen it or use the Password Generator.
Example
The example fills in realistic values and runs the tool. Select Try an example above to see it.
When it helps
- Choosing a new password.
- Teaching password security.
- Testing password policies.
Questions
How is crack time estimated?
Assuming an offline attacker trying 10 billion guesses per second against a fast hash. Real attacks are faster for common passwords.
What makes a strong password?
Four or more random words, or 16+ random characters, unique to each site and stored in a password manager.
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