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Password Generator
Generate strong, random passwords locally in your browser.
Security
Password Strength Checker
Type or paste a password and get an instant strength score, entropy estimate, and concrete feedback — everything runs locally so your password never leaves the browser.
Check a password
Result
- Score
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- Entropy
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- Length
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- Character classes
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How it works
Strength scoring, locally
Length and variety
Longer passwords with more character classes (lowercase, uppercase, digits, symbols) score higher. A short password made of only one class caps out fast no matter what you fill it with.
Patterns and common choices
Repeated characters, sequential runs (abc, 123), and known common passwords (password123, qwerty) are penalised heavily — they're the first thing an attacker tries.
Entropy in bits
Entropy measures the search space: log2 of (pool size ^ length). Every added bit doubles the work for a brute-force attack. 80+ bits is a strong target.
Questions
Password strength FAQ
What does the strength score mean?
It's a 0–100 rating based on length, character variety, and penalties for common or patterned choices. 0–19 is very weak, 20–39 weak, 40–59 fair, 60–79 strong, 80–100 very strong.
How is entropy estimated?
Entropy = log2(pool size ^ length), where the pool is the combined set of character classes present. More bits means exponentially more guesses for an attacker — 80+ bits is a strong target.
Is my password sent to a server?
No. The entire check runs in your browser. Nothing you type is uploaded, stored, or logged — your password never leaves your device.