Password Strength Checker – Test a Password Privately
Checked entirely in your browser — this password is never sent anywhere.
- At least 12 characters
- Lowercase letter
- Uppercase letter
- Number
- Symbol
- Not an obvious pattern
About Password Strength Checker
Type a password and see how strong it actually is: an entropy-based score, which character types it uses, and warnings about the predictable patterns attackers try first.
Most strength meters just count character types, which is why P@ssw0rd1 often scores well despite being one of the first things any attacker tries. This one estimates entropy — how much genuine unpredictability the password contains — and separately flags recognisable patterns like keyboard runs, repeated characters and common substitutions.
The check happens entirely in your browser. Nothing is typed into a network request, so no password you test here is transmitted anywhere. Any strength checker that does not make that guarantee should not be given a real password.
What you can use it for
- Check whether a password you already use is as strong as you assumed.
- Compare two candidate passwords before choosing one.
- See why a password a site rejected was considered weak.
- Show someone concretely why a longer passphrase beats a short complex password.
- Test a memorable passphrase before adopting it.
How it works, step by step
- 1
Type a password
Enter the password you want to assess. It stays in your browser.
- 2
Read the score
The strength rating is based on estimated entropy, not just a character-type count.
- 3
Check the breakdown
See which character classes are present and which are missing.
- 4
Act on the warnings
Patterns like keyboard runs and repeated characters are flagged, since attackers test those first.
Frequently asked questions
Is it safe to type my real password here?
The check runs entirely in your browser and nothing is uploaded or logged. Even so, good practice is to test a close variant rather than a live password you rely on.
What is entropy?
A measure of unpredictability, in bits. Each additional bit doubles the work of guessing. It is a better guide than counting character types, because it accounts for how large the pool of possible passwords actually is.
Why does my complex password score poorly?
Usually because it follows a predictable pattern. A dictionary word with letters swapped for numbers, a keyboard run, or a word followed by a year are all things cracking tools try early, so they add far less real strength than their appearance suggests.
Is a long passphrase better than a short complex password?
Almost always. Several unrelated words are both easier to remember and harder to crack than a short string of substituted symbols.
Does this check whether my password has been breached?
No. It analyses the password's structure only. Checking against breach databases would require sending data about it, which would defeat the purpose of an on-device tool.