🔒 Free AES Encryptor / Decryptor - Online AES Encryption | ToolZen

1. Is AES encryption secure?

AES (Advanced Encryption Standard) is a NIST-approved symmetric encryption standard used worldwide. AES-256 is considered highly secure for government and commercial use.

2. Is my data sent to your server?

No. All encryption and decryption is performed locally in your browser. CBC mode uses the Web Crypto API and ECB mode uses the aes-js library. Your data never leaves your device.

3. What is AES-CBC mode?

AES-CBC (Cipher Block Chaining) uses an Initialization Vector (IV) to randomize the encryption so that identical plaintext blocks produce different ciphertext. This prevents patterns from leaking and is the recommended mode for most use cases.

4. What is AES-ECB mode?

AES-ECB (Electronic Codebook) encrypts each 16-byte block independently. It is deterministic — identical plaintext blocks always produce identical ciphertext blocks — which can leak patterns. CBC is recommended for security; ECB may be used for compatibility with legacy systems.

5. How do I decrypt my data later?

You need two things: the encrypted text and the same secret key. For CBC mode, the IV is automatically embedded in the output. For ECB mode, no IV is needed.