Encrypt / Decrypt
Encrypt, decrypt, sign and verify using AES, DES, RC4, RSA and ECDSA — all client-side
About Encrypt & Decrypt Text Tool
The Encrypt & Decrypt Text tool provides symmetric encryption and decryption capabilities plus HMAC message authentication directly in your browser. Protect sensitive text with AES, DES, Triple DES, or Rabbit encryption, and digitally sign or verify data using HMAC algorithms — all without sending a single byte to any server. Every cryptographic operation runs client-side using the CryptoJS library.
Understanding Symmetric Encryption
Symmetric encryption uses the same key for both encryption and decryption. This makes it fast and efficient for protecting data at rest or in transit when both parties share a secret key. AES (Advanced Encryption Standard) is the gold standard, adopted by governments and enterprises worldwide. DES and Triple DES remain available for legacy system compatibility, while Rabbit is a stream cipher optimized for software performance. This tool lets you experiment with all of these algorithms to understand their behavior and test your implementations.
Key Features
- AES-256 encryption — the industry standard for symmetric encryption, used by banks, governments, and security-critical applications worldwide.
- Multiple algorithms — supports AES, DES, Triple DES (3DES), and Rabbit cipher for different security and compatibility needs.
- HMAC signing — generate and verify HMAC-SHA256 message authentication codes to ensure data integrity and authenticity.
- Digital signatures — sign text and verify signatures to detect tampering or unauthorized modifications.
- Client-side only — all cryptographic operations run locally in your browser using CryptoJS. Zero server communication.
- Copy results — one-click copy for encrypted text, decrypted output, or HMAC signatures.
How to Encrypt and Decrypt
- Choose operation — select Encrypt, Decrypt, Sign, or Verify from the mode selector.
- Select algorithm — choose AES, DES, 3DES, or Rabbit for encryption/decryption operations.
- Enter data — type or paste the text you want to process and provide the secret key or passphrase.
- Process — click the action button to encrypt, decrypt, sign, or verify.
- Copy result — copy the output to your clipboard for use in your application or communication.
Security Best Practices
Always use AES-256 for new projects — DES and 3DES should only be used for legacy compatibility. Choose strong, unique passphrases with at least 16 characters. Never share encryption keys over the same channel as the encrypted data. For production systems, use established cryptographic libraries with proper key derivation functions (PBKDF2, Argon2) rather than raw passphrase encryption. This tool is excellent for testing, learning, and quick encryption tasks.
Real-World Use Cases
- Encrypting sensitive notes, passwords, or API keys before sharing them over email or messaging apps.
- Decrypting AES-encrypted messages received from colleagues, automated systems, or webhook payloads.
- Generating HMAC-SHA256 signatures for webhook payload verification during API development.
- Testing encryption and decryption flows before implementing them in production application code.
- Learning about symmetric encryption algorithms and their behavior with hands-on experimentation.
Frequently Asked Questions
Which algorithm should I use?
Use AES-256 for all new projects. It is the global standard for symmetric encryption with no known practical vulnerabilities. DES and 3DES are provided only for legacy compatibility.
Is my data safe?
Yes. All encryption and decryption operations happen entirely in your browser using CryptoJS. Your text, keys, and results are never transmitted to any server.
Can I use this for production encryption?
This tool is ideal for testing, debugging, and learning. For production systems, use established cryptographic libraries with proper key management, key derivation, and IV handling.
What is HMAC and when should I use it?
HMAC (Hash-based Message Authentication Code) verifies both data integrity and authenticity. Use it when you need to ensure a message hasn't been tampered with, such as webhook signature verification.
What is the difference between AES and DES?
AES uses a 256-bit key and is considered unbreakable with current technology. DES uses a 56-bit key and can be cracked in hours. 3DES applies DES three times but is still slower and weaker than AES.