Password Strength Checker
Password Strength Checker evaluates your password in real-time with a score, entropy estimate, time-to-crack and specific improvement tips — all locally in your browser.
Last updated: July 2026
A password strength checker evaluates how resistant a password is to guessing and brute-force attacks. It scores length, character diversity, common patterns and estimated entropy (bits). A score of 80+ is strong; below 40 is weak.
🔒 Your password is analysed entirely in your browser — it never leaves your device. No data is stored or transmitted.
How to use Password Strength Checker
- Type a password to test.
- Watch the strength score, entropy and estimated crack time update live.
- Read the specific suggestions to make it stronger.
Frequently asked questions
Is my password sent anywhere?
No — the analysis runs entirely in your browser. The typed password never leaves your device.
What is entropy?
Entropy measures unpredictability in bits. Higher entropy means more guesses needed.
What makes a password strong?
Length matters most — aim for 12+ characters mixing uppercase, lowercase, digits and symbols.
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