Uttir

Password Strength Checker

See how strong a password really is — entropy, time-to-crack, and a list of issues, all computed in your browser.

Password Strength Checker — A strong password is the single biggest factor in whether an account gets compromised. This checker scores any password in real time using Shannon entropy, then layers on penalties for common patterns: keyboard sequences (qwerty, 1234), long repeats (aaaa, 1111), all-numeric or all-lowercase strings, and the most-leaked passwords on the internet.

Your password is analyzed locally in your browser. It is never sent to a server, logged, or stored anywhere.

What is password strength checker?

A strong password is the single biggest factor in whether an account gets compromised. This checker scores any password in real time using Shannon entropy, then layers on penalties for common patterns: keyboard sequences (qwerty, 1234), long repeats (aaaa, 1111), all-numeric or all-lowercase strings, and the most-leaked passwords on the internet.

The result is a 0–100 score, a strength bucket, the number of bits of entropy, a human-readable time-to-crack estimate at modern offline-attack speeds, and a list of specific issues if any were found. Every calculation runs in your browser — your password is never sent to a server.

How to use it

  1. Type or paste a password

    Use the show/hide eye to verify what you typed.

  2. Read the verdict

    Score, entropy, strength bucket, and a plain-English verdict appear as you type.

  3. Fix the issues

    If issues are listed, lengthen the password or add a missing character class.

Examples

A weak password

Lowercase letters, common word, 8 characters.

password

Result: Very weak · ~6 bits effective · instantly crackable · common-password match

A strong password

16 characters, mixed case, numbers, symbols.

T7$mK9p!qL2v#R4n

Result: Very strong · ~104 bits · centuries to crack

Frequently asked questions

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