Check How Strong Your Password Is — Entropy & Crack Time
Type a password and see its entropy, estimated crack time, and exactly what to improve. Your password never leaves your device.
Nothing is uploaded — runs entirely in your browserWhy check password strength?
Data breaches expose millions of passwords every year. Weak passwords are cracked in seconds. Reused passwords let attackers access multiple accounts. Knowing your password's real strength — not just what a website's colored bar says — is the first step to better security.
How is strength calculated?
The tool calculates entropy in bits based on password length and character diversity (lowercase, uppercase, numbers, symbols). It then estimates crack time assuming a high-end attacker with a trillion guesses per second. This gives you a realistic picture of how long your password would survive a targeted attack.
Is it safe to type my real password?
Yes. The analysis runs entirely in your browser. No password is sent to any server, logged, or stored. For extra caution, you can type a password with the same length and character types as your real one — the entropy and crack time will be identical.
Free, instant, and 100% private. No account needed.
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