Password Strength Tester
Test your password's entropy against character pool size and common password lists. Runs entirely offline.
What is Password Strength Tester?
Password strength is measured in bits of entropy — the log2 of the number of possible passwords matching your character set and length. 60 bits is the minimum NIST recommendation; 80+ resists nation-state attacks. This tool computes entropy, checks against the 10 most common passwords, and suggests specific improvements.
Frequently asked questions
Is my password sent anywhere?▼
No. All scoring happens in your browser. Nothing leaves your device.
What's the minimum strength?▼
60 bits of entropy is NIST's minimum for human passwords. 80+ is recommended for sensitive accounts.
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