Encrypt and decrypt text using AES, DES, TripleDES, and Rabbit algorithms. Secure your data with industry-standard encryption methods and multiple cipher modes.
Encrypting or decrypting text is straightforward: Type or paste your plaintext into the input box if you want to encrypt, or paste encrypted ciphertext if you want to decrypt. Enter your encryption key — this is the secret value that controls the transformation. Use a strong key of at least 16 characters (128 bits) for AES encryption; shorter keys reduce security exponentially. Choose your algorithm from the dropdown: AES for modern security, TripleDES for legacy compatibility, or Rabbit for lightweight stream encryption. Select the cipher mode — CBC (Cipher Block Chaining) for general use, ECB only when compatibility with existing systems requires it. Pick your output encoding format: hexadecimal for easy copying, Base64 for URL-safe transmission, or raw binary for storage. Click Encrypt or Decrypt depending on your goal. The result appears in the output box — copy it and use it wherever needed.
The cipher mode determines how each block of plaintext is transformed. ECB (Electronic Codebook) encrypts each block independently using the same key — identical plaintext blocks produce identical ciphertext blocks, which leaks patterns in the data. A famous example is the ECB-encrypted Linux Tux logo where the outline remains visible because large areas of uniform color produce repeating ciphertext blocks. CBC (Cipher Block Chaining) XORs each plaintext block with the previous ciphertext block before encryption, eliminating pattern leakage. It requires an Initialization Vector (IV) — a random value unique to each encryption operation — appended to the ciphertext for decryption. CTR (Counter) mode converts a block cipher into a stream cipher by encrypting successive counter values and XORing them with plaintext. CTR allows parallel encryption and decryption, supports random access to any block position, and doesn't require padding. For new implementations, prefer CBC with a random IV or CTR mode over ECB under any circumstances.
No encryption algorithm can protect data if the key is weak, reused, or exposed. AES-256 with a poor 8-character password is less secure than AES-128 with a cryptographically random 32-byte key. Key derivation functions like PBKDF2, scrypt, or Argon2 transform passwords into proper-length keys through iterative hashing with salt — our tool uses direct key input for simplicity, but production systems should always derive keys properly. Never reuse IVs with the same key in CBC mode; reusing an IV exposes XOR relationships between plaintexts. Never hardcode encryption keys in source code — use environment variables, secret managers (AWS Secrets Manager, HashiCorp Vault), or hardware security modules (HSM). Rotate keys periodically: every 90 days for high-security applications, annually for standard use. When a key is compromised, all data encrypted with that key must be considered potentially exposed and re-encrypted with a new key.
Encryption is reversible — you encrypt with a key and decrypt with the same key. Hashing is one-way — you compute a hash from data but cannot recover the original. Use encryption when you need to retrieve the original data later. Use hashing for password storage and integrity verification.
AES is the default choice for virtually all applications — it's the NIST standard, used by governments and financial institutions worldwide. TripleDES provides backward compatibility with older systems. Rabbit is a fast stream cipher suitable for resource-constrained environments. Avoid DES and RC4 — both have known vulnerabilities.
Yes — all processing happens locally in your browser. Your text never leaves your device, so no server can intercept it. However, encryption is only as strong as your key. Use a long, random key and never share it through insecure channels.
This tool is designed for testing, learning, and development workflows. Production systems handling sensitive data should use well-tested cryptographic libraries (libsodium, OpenSSL, Web Crypto API) with proper key management, authenticated encryption (AES-GCM), and security audits.
Garbled output usually means the key, algorithm, mode, or encoding doesn't match what was used for encryption. Verify all parameters are identical between encryption and decryption operations. Check that the IV (if used) is correctly preserved and prepended to the ciphertext.
AES supports 128-bit (16 bytes), 192-bit (24 bytes), and 256-bit (32 bytes) keys. AES-128 provides 2^128 possible keys — computationally infeasible to brute-force with current technology. AES-256 offers higher security margin but is slightly slower. Both are considered secure for current and near-future applications.