About RC4
RC4 (also known as ARC4) is a widely-used stream cipher designed by Ron Rivest. It is used in popular protocols such as SSL and WEP. Although remarkable for its simplicity and speed, the algorithm's history doesn't inspire confidence in its security.
Input: text. Output: text.
Format reference: RC4 background and specification
Example
Use “Try example” to load this public sample and its settings, then run it.
Settings used in this example
| Parameter | Example value | Input and choices |
|---|---|---|
| Passphrase | {"option":"UTF8","string":"Key"} | Key/text encoding: UTF8, UTF16, UTF16LE, UTF16BE, Latin1, Hex, Base64 |
| Input format | UTF8 | Latin1, UTF8, UTF16, UTF16LE, UTF16BE, Hex, Base64 |
| Output format | Hex | Latin1, UTF8, UTF16, UTF16LE, UTF16BE, Hex, Base64 |
Input
Plaintext
Result
bbf316e8d940af0ad3
Parameters
| Parameter | Default value | Input and choices |
|---|---|---|
| Passphrase | {"option":"UTF8","string":""} | Key/text encoding: UTF8, UTF16, UTF16LE, UTF16BE, Latin1, Hex, Base64 |
| Input format | Latin1 | Latin1, UTF8, UTF16, UTF16LE, UTF16BE, Hex, Base64 |
| Output format | Latin1 | Latin1, UTF8, UTF16, UTF16LE, UTF16BE, Hex, Base64 |
Before interpreting the result
Use the exact key encoding, mode, padding and IV expected by the source system. Historical ciphers are useful for learning and analysis. Encoding alone provides no confidentiality.
How to use this page
- Paste your input or open a local file.
- Adjust tool options if needed, then choose Run tool.
- Copy the result or download the original output bytes.
Inputs and results are not added to the public catalogue or saved in the URL. Processing happens in your browser; HTTP Request and DNS over HTTPS send the requests you explicitly run. Files up to 128 MiB can be opened; decompression and image tools may have smaller processing limits. Large results have a shortened preview. Text and HTML downloads use UTF-8; binary downloads preserve output bytes. Pasted text follows browser newline handling; open a file when exact input bytes matter.