Developer Tools
Decrypt RC4 ciphertext instantly with the same passphrase.
Use this RC4 Decrypt tool to reverse RC4-encrypted Base64 text using the original passphrase. It is useful for legacy compatibility testing, reversible development workflows, encrypted sample validation, and checking whether RC4-encrypted values can be decoded back into readable text correctly.
Use this RC4 Decrypt tool to reverse RC4-encrypted Base64 text using the original passphrase. It is useful for legacy compatibility testing, reversible development workflows, encrypted sample validation, and checking whether RC4-encrypted values can be decoded back into readable text correctly.
Use rc4 decrypt when you need a fast browser-based result without extra setup. It works well for quick checks, one-off tasks, and routine formatting or calculation work.
Read step-by-step usage guidance, best practices, and common mistakes.
See common questions and answers about input, output, and tool usage.
Review practical input and output examples before running the tool.
Find similar and supporting tools for adjacent actions and follow-up tasks.
Input
legacy-key Base64 encrypted text
Output
hello world
Useful for reversing an RC4-encrypted sample.
Input
demo-pass Base64 encrypted text
Output
api_key=12345
Useful for checking reversible RC4 output on short strings.
Fix: Use exactly the same passphrase that was used during encryption.
Fix: Paste Base64 ciphertext produced by the matching RC4 encrypt flow.
Fix: Put the passphrase first and the ciphertext below it.
Fix: This usually means the passphrase or ciphertext format is wrong.
Fix: Use the matching decrypt tool for the actual cipher.
It decrypts RC4 Base64 ciphertext back into readable text.
Yes. The exact same passphrase is required.
Use Base64 ciphertext produced by the matching RC4 encrypt flow.
The most common reasons are the wrong passphrase or invalid ciphertext format.
The reverse tool is RC4 Encrypt.