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Security
Custom Polybius Square
Build a 5×5 Polybius square with a key letter and encrypt/decrypt messages using numeric coordinates.
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Related Tools
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Password Generator
Generate strong, random passwords with custom length, uppercase letters, numbers and symbols. Generated in the browser — no data leaves your device.
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Encrypt Text
Apply classic ciphers (Caesar, ROT13, Atbash) or Base64. Useful for puzzles, CTFs and testing — do not use for real security.
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Password Strength Checker
Check the strength of a password with entropy calculation, common-password check and improvement tips. Runs in your browser — no data is sent.