Free Password Strength Checker
Think your password is strong? Most people overestimate. The Password Strength Checker analyzes any password with entropy-based scoring: it measures length and character variety, then penalizes common passwords, keyboard sequences, repeated characters and predictable patterns. You get a 0–100 score, an entropy estimate, and a realistic crack-time figure — so you can see exactly how your password holds up against modern guessing attacks.
Analysis happens as you type — the password never leaves this page.
How to Use the Password Strength Checker
- Type a password into the field above.
- Watch the live score, entropy estimate, and crack-time calculation update.
- Review the breakdown — length, character variety, and detected weaknesses.
- Follow the suggestions to strengthen weak passwords, then generate a new one.
Features
Live scoring as you type; 0–100 score with strength labels; entropy estimate in bits; crack-time estimate at 10 billion guesses per second; detection of common passwords, sequences, repeats and keyboard patterns; concrete improvement suggestions.
Benefits & Use Cases
Use it to audit your current passwords, to show friends and family what 'strong' really means, or to sanity-check password policies you are designing for an app. It is also a quick reality check before reusing a 'clever' password you invented.
Tips
A high score does not help if you reuse the password — uniqueness matters as much as strength. If your password scores under 60, generate a fresh one instead of tweaking it. No checker can detect a password already leaked in a breach, so verify that separately.
Frequently Asked Questions
Is it safe to type my real password here?
Yes. All analysis happens locally in your browser with JavaScript — your password is never sent to any server, stored, or logged anywhere.
How is the strength score calculated?
The tool estimates entropy from length and character variety, then subtracts penalties for common passwords, sequences like '123', repeated characters, and keyboard patterns. The result is mapped to a 0–100 score.
What does crack time mean?
It is an estimate of how long brute force would take at 10 billion guesses per second — roughly what a single modern GPU can attempt. Real attackers use many GPUs, so treat it as an optimistic upper bound.
My password scored 100. Am I safe?
It is strong against guessing, but strength is only one factor. Do not reuse it anywhere, enable two-factor authentication, and make sure it has not appeared in a known data breach.
Why was my long password rated weak?
Probably because it matched a common password or pattern. Attackers try dictionary words, keyboard walks, and leaked passwords first — a long but predictable password falls fast.
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