AES Encrypt/Decrypt
Encrypt or decrypt text with AES-GCM, using a password. Uses your browser's real cryptography engine — nothing is sent anywhere.
About this tool
Uses AES-256-GCM via the Web Crypto API. Your password is stretched into a key with PBKDF2-SHA-256 at 600,000 iterations, the level OWASP currently recommends, which makes each password guess slow for an attacker. A fresh random salt and IV are used every time you encrypt, so encrypting the same text twice gives different output; that's expected and correct. GCM also detects tampering: if even one character of the encrypted text is changed, decryption fails rather than producing garbled text.
To decrypt, press Use result as input (or paste the encrypted text in and choose Decrypt) and enter the same password. Text encrypted by earlier versions of this tool, which used 100,000 iterations, still decrypts. Because key stretching takes a moment, the result updates shortly after you stop typing. The strength of the encryption depends on your password, so use a long one, such as a passphrase of four or more random words.
This is real, reputable cryptography, not a toy cipher — but for anything genuinely high-stakes, use dedicated, audited encryption software rather than a browser tool.