Difference Between AES and RC4 (With Table)

It is critical to preserve our confidential information while we trade data over the Internet. To reestablish data security, cryptographic techniques like AES and RC4 are utilised. Cryptologists devised this excellent technique that is difficult for a cryptanalyst by mixing elements from mathematics and computer science.

AES vs RC4

The main difference between AES and RC4 is that AES is a block cypher that uses a set key and a formula to encrypt discrete blocks of data. On the other hand, RC4 is a stream cypher that does not have a distinct block size.

AES is a cypher, which means it encrypts and decrypts data. When you send files through secure communication protocols like HTTPS, FTPS, SFTP,OFTP, or AS2, there’s a strong chance your information will be encrypted with AES 256, 192, or 128-bit cyphers. 

Due to its speed and simplicity, the RC4 encryption has become the most extensively used stream cypher, and it is used in protocols such as Wired Equivalent Privacy, Secure Sockets Layer, and Transport Layer Security (TLS).
In the current implementation of TLS, RC4 is manifestly flawed and hazardous to use.

Comparison Table Between AES and RC4

Parameters of comparison
DefinitionThe Advanced Encryption Standard (AES) is a block cypher that is symmetric.Rivest Cipher 4, also known as Rivest Cipher 4, is a symmetric stream cypher.
OriginIn 1997, an open competition was held to design AES.RC4 was created by Ron Rivest in 1987.
SecurityAES is a more safe encryption algorithm than RC4.AES is more secure than RC4.
Key sizes128, 192, and 256 bits
64 or 128 bits
Applications SSL, TSL, etc.NASA, NIST, etc 

What is AES?

The Advanced Encryption Standard is all around you and you’re not even aware of it. It is in the background, doing its thing, when you fill out government paperwork online (passport applications, drivers licence renewals, etc. ), when you store personal information on a website (Facebook, Twitter, etc. ), and even when you use your VISA or bank card to make a purchase.

The Advanced Encryption Standard (AES) is a cypher, which means it is a method or procedure for converting raw data (typically human readable) into unreadable data.

AES is a symmetric key block cypher that employs a block cypher. To convert plain text to ciphertext, it is encoded in block sizes. The maximum bit size is 128 bits, with key sizes of 128, 192, and 256 bits.

The amount of rounding depends on the size of the key. For 128 bits, there are 10 rounds, 12 rounds for 192 bits, and 14 rounds for 256 bits. AES128, AES192, and AES256 are their names.

Encryption is the name for this portion of the procedure. To modify the data in a unique way, the approach uses a known, external piece of information called a key. Your computer login password, for example, or the password to your bank account, are both examples of passwords.

Furthermore, the technique is reversible, which means it can be used to restore the information to its original state.

What is RC4?

Rivest Cipher 4 (commonly known as RC4) is a type of stream cypher. It uses an algorithm to encrypt messages one byte at a time.

There are many other stream cyphers, but RC4 is one of the most popular. It’s easy to use and works rapidly, even with enormous amounts of data. You’ve probably met RC4 encryption if you’ve ever used a TSL (transport layer security) or SSL (secure socket layer) application.

The RC4 encryption algorithm was created by Ron Rivest in 1987. He wanted to keep the cipher’s rules hidden, and if his strategy worked, he would have devised one of the safest techniques for protecting information. Unfortunately, his ideas did not come to fruition. RC4 encryption isn’t widely used. In fact, the Internet Engineering Task Force has expressly forbidden the usage of RC4 in certain areas.

In 1994, an anonymous person in a public place posted a detailed description of the cipher’s rules. We know a lot more about how RC4 works now that the regulations are out in the open. Unfortunately, this also means that hackers have a better understanding of how to break it.

The encryption tools used by RC4 are complex. They usually have 256 bytes, and the text is passed through a series of mathematical criteria before being considered complete.

If you intercept RC4-encrypted data, you’ll see nothing but zeroes and ones. However, if you have the right key, you can turn that data into useful knowledge.

Main Differences Between AES and RC4

  1. Rivest Cipher 4 is a stream cypher, whereas AES, or Advanced Encryption Standard, is a block cypher.
  2. In comparison to RC4, AES is more secure in terms of security.
  3. AES was created after RC4, with the former beginning in 1997 and the later beginning in 1987.
  4. AES has key sizes of 128, 192, and 256 bits, while RC4 uses key sizes of 64 and 128 bits.
  5. AES uses a complicated algorithm, but RC4 uses a basic approach.


It is crucial to check the security of our data when we use the Internet to transmit vital information. Our data is encrypted using the encryption technique, which ensures the confidentiality of our sensitive information. AES and RC4 are two algorithms that can be used to keep our information safe from prying eyes.

AES is regarded one of the most complex algorithms, taking billions of years for an expert to decipher using modern computer technologies, whereas RC4 is an older version that was introduced in 1987, a decade before AES.

AES is classified as a block cypher, whereas RC4 is classified as a stream cypher. AES is a software and hardware implementation of a publicly stated algorithm. RC4 is, on the other hand, covered by trademark protection.

Until it was placed into the public domain, RC4 remained underwater. NASA and the National Institute of Standards and Technology (NIST) have adopted AES for their high-security encryption. While RC4 is used in SSL (1995), WEP (1997), and TLS (1999), WPA is not (2003). AES is slower than RC4.


  1. https://citeseerx.ist.psu.edu/viewdoc/download?doi=
  2. https://link.springer.com/article/10.1007/s10623-008-9206-6