About this AES tool
Enter a passphrase and plaintext, hit Encrypt to get one Base64 ciphertext; paste it back with the same passphrase to restore the original. It uses the browser's native WebCrypto AES-GCM-256: the passphrase is turned into a key via PBKDF2-SHA-256 (150,000 iterations, 16-byte random salt), every encryption draws a fresh 12-byte random IV, and the GCM authentication tag makes tampered ciphertexts fail to decrypt.
The ciphertext is Base64 of salt (16 bytes) + IV (12 bytes) + ciphertext, so the whole string travels through chat apps or notes, and the recipient decrypts it here with the same passphrase. Everything runs locally — the passphrase and plaintext never leave your device. Because each encryption uses a random IV, encrypting the same plaintext twice yields different ciphertexts; that is expected.