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Technical Jan 30, 2026 9 min read

AES-256 Encryption Explained Simply

What is Encryption?

Encryption is the process of converting readable data (plaintext) into an unreadable format (ciphertext) using a mathematical algorithm and a key. Only someone with the correct key can convert it back.

Think of it like a lockbox: you put your data inside, lock it with a key, and only the matching key can open it again.

What Does AES-256 Mean?

AES stands for Advanced Encryption Standard. It was selected by the U.S. National Institute of Standards and Technology (NIST) in 2001 after a 5-year competition. 256 refers to the key length in bits.

  • AES-128: 128-bit key — very secure
  • AES-192: 192-bit key — more secure
  • AES-256: 256-bit key — maximum security, used by governments and military

How Strong is AES-256?

A 256-bit key means there are 2^256 possible combinations. That's:

115,792,089,237,316,195,423,570,985,008,687,907,853,269,984,665,640,564,039,457,584,007,913,129,639,936 possible keys

If every computer on Earth tried a billion keys per second, it would take longer than the age of the universe to try them all. AES-256 is practically unbreakable.

How SecureVault Uses AES-256

  1. Key Derivation: Your master password is processed through PBKDF2 with 100,000+ iterations to create a 256-bit encryption key
  2. Encryption: Each password/file is encrypted with this key using AES-256 in CBC mode
  3. Storage: Only the encrypted ciphertext is stored on the server
  4. Decryption: When you log in, your master password re-derives the key to decrypt your data locally

Zero-knowledge: The server never sees your master password or encryption key. It only stores encrypted blobs that are meaningless without your password.

AES-256 vs Other Encryption

  • DES/3DES: Outdated, 56/168-bit keys — considered insecure since the 2000s
  • RSA: Asymmetric encryption used for key exchange, not bulk data encryption
  • ChaCha20: Modern alternative, similar strength — used by some VPNs
  • AES-256: The industry standard for 25+ years, battle-tested and universally trusted

Common Misconceptions

"Encryption can always be broken with enough computing power"

Not AES-256. Even quantum computers (as currently theorized) would only reduce the effective security to 128 bits — which is still unbreakable.

"If the government uses it, there must be a backdoor"

AES is an open standard. The algorithm is public and has been analyzed by thousands of cryptographers worldwide. No backdoor has ever been found.

The Bottom Line

AES-256 is the gold standard of encryption for good reason. When SecureVault encrypts your passwords with AES-256, they're protected by the same algorithm that safeguards classified government documents. Your data is safe.

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