Analyse password strength

Evaluate a password for length, patterns, commonness, and breach exposure.

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ToolPassword Strength Analyzer
Input
Output
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Preview

How it works

The candidate is scored using length, character diversity, repetition, common-pattern, and breached-password signals. Pattern penalties approximate likely guesses; they cannot prove that a secret has never appeared in a breach corpus.

  • Length and blocklist checks are more predictive than arbitrary symbol rules.

Worked example

Weak Password
Analyze a common weak password
Input
											password123
Output
												=== Password Strength Analysis ===

Password length: 11
Strength: Very Strong (80/100)
Entropy: 56.9 bits
Character pool: 36 characters
Estimated crack time: 76 days (10B guesses/sec)

Character types:
  Lowercase: Yes
  Uppercase: No
  Numbers: Yes
  Symbols: No
  Spaces: No

Recommendations:
  - Use at least 12 characters
  - Add uppercase letters
  - Add special characters
  - Use more character types

When to use this

Signup feedback, password resets, and policy reviews analyze candidate secrets.

Edge cases

  • Password1! satisfies character rules but is common.
  • A long quotation can score poorly because it is searchable.
  • A random password may look unusual while still failing a breached-secret list.

References