AES Encrypt & Decrypt

AES-256-GCM (Advanced Encryption Standard with Galois/Counter Mode) is a symmetric authenticated encryption algorithm. It provides both confidentiality and integrity protection, ensuring that tampered ciphertext will fail to decrypt.

How It Works

1. Key Derivation: Your password is stretched using PBKDF2 with SHA-256 and 100,000 iterations to produce a 256-bit AES key. A random 16-byte salt ensures uniqueness each time.
2. Encryption: AES-GCM encrypts the plaintext with a random 12-byte initialization vector (IV) and produces an authentication tag.
3. Output: The salt, IV, and ciphertext are concatenated and base64-encoded into a single portable string.

Security Notes

• The strength of the encryption depends entirely on the strength of your password. Use long, random passwords.
• Each encryption produces a unique ciphertext even for identical plaintext and password, due to random salt and IV.
• GCM mode detects tampering — if even one byte of the ciphertext is modified, decryption will fail.
• This tool uses the browser's native Web Crypto API, which is implemented in optimized native code.