AES Encrypt/Decrypt Online - EXUtil Extended Utilities
Free online AES symmetric encryption and decryption tool. Supports ECB/CBC/CFB/OFB/CTR modes with configurable padding and Base64/Hex output formats.
How to use
- Paste or import the content you want to process.
- Choose an available action and run the tool.
- Review the result, then copy or download the output.
Frequently asked questions
- AES modes?
- ECB, CBC, CFB, OFB, CTR. CBC most common, CTR supports parallel encryption.
- Same key for encrypt/decrypt?
- Yes. AES is symmetric. Keep key secure - if leaked, data is compromised.
- AES-128 vs AES-256?
- AES-256 more secure but slower. AES-128 is secure; AES-256 for highest security.
- What is IV?
- Initialization Vector - random value ensuring same plaintext encrypts differently. Must be random and unique.
- AES for passwords?
- No. AES is reversible. If key leaks, all passwords leak. Use Bcrypt for passwords.
References
Technical standards and official documentation related to this tool.
- NIST FIPS 197 - Advanced Encryption Standard
The NIST standard defining the AES block cipher.