AES Encryption / Decryption

AES (Advanced Encryption Standard) is a symmetric encryption algorithm standardized by NIST in 2001. AES-256 uses a 256-bit key to encrypt data in 128-bit blocks, providing strong security for sensitive information.

Supported Modes

• AES-256-CBC (Cipher Block Chaining) — Each block is XORed with the previous ciphertext block before encryption. Requires a 16-byte IV. Does not provide authentication (tamper detection).
• AES-256-GCM (Galois/Counter Mode) — Provides both encryption and authentication (integrity verification). Requires a 12-byte IV/nonce. Recommended for most applications.

Key Derivation

This tool uses PBKDF2-HMAC-SHA-256 to derive a 256-bit key from your password. A random 16-byte salt is generated for each encryption. The encrypted output is formatted as: salt (16B) + IV + ciphertext, all Base64-encoded.

Encrypt

1. Enter the plaintext you want to encrypt.
2. Enter a strong password.
3. Select AES mode (GCM recommended).
4. Click "Encrypt" — the encrypted Base64 output includes salt, IV, and ciphertext.
5. Share the encrypted output and password with the recipient (via a secure channel).

Decrypt

1. Paste the encrypted Base64 string.
2. Enter the same password used for encryption.
3. Select the same AES mode and iterations.
4. Click "Decrypt" — the original plaintext is recovered.