RC4 Encryption Tool
Encrypt text using RC4 stream cipher with variable key size. Free online RC4 encryption.
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What is RC4 Encryption?
RC4 (Rivest Cipher 4) is a stream cipher designed by Ron Rivest in 1987. It uses variable key sizes from 40 to 2048 bits and was widely used in protocols like WEP and SSL.
How to Use RC4 Encryption
When to Use RC4 Encryption
How RC4 Encryption Works
RC4 generates a pseudorandom stream of bytes (keystream) which is XORed with the plaintext to produce ciphertext. It uses a simple and fast algorithm based on permutation and XOR operations.
Common Use Cases
- Legacy protocol support
- Educational purposes
- Understanding stream ciphers
Security Note
⚠️ RC4 has known vulnerabilities and is prohibited in TLS. Do not use for new applications. Use AES or ChaCha20 instead.
FAQs
1 Is RC4 secure?
No, RC4 has multiple security vulnerabilities and biases. It is deprecated in modern protocols.
2 Why was RC4 popular?
RC4 was popular due to its simplicity and speed, but security flaws led to its deprecation.