Security
String Obfuscator
The String Obfuscator encodes strings into obfuscated representations such as character code arrays, Unicode escape sequences, hexadecimal escape sequences, or XOR-encoded strings. It is used to make hardcoded strings in source code less immediately readable, hide simple API keys or tokens from casual inspection, or generate alternate representations for analysis. Note that obfuscation is not encryption – a determined reader can always reverse it.
What is string obfuscation?
String obfuscation transforms a readable string into a harder-to-read encoded form while preserving the ability to recover the original at runtime. Common techniques include: character code arrays (the string is split into ASCII/Unicode code points and stored as an integer array), Unicode escape sequences (\u0048\u0065\u006C\u006C\u006F for 'Hello'), hexadecimal escape sequences (\x48\x65\x6C\x6C\x6F), Base64 encoding, and XOR with a repeating key (each byte XORed with a key byte). Obfuscation is used in JavaScript minifiers to hide strings, in license key systems to obscure validation logic, and in CTF (Capture the Flag) challenges. It is not a security control against a determined attacker.
How does the tool work?
The tool offers several obfuscation modes. In 'char codes' mode, each character is mapped to its Unicode code point and the array of integers is output as JavaScript source (e.g. String.fromCharCode(72,101,108,108,111)). In 'Unicode escape' mode, each character becomes a \uXXXX sequence. In 'hex escape' mode, each byte becomes a \xXX sequence (for ASCII strings). In 'XOR' mode, the user provides a key; each byte of the input is XORed with the corresponding byte of the key (cycling through the key) and the result is hex-encoded; a matching decoder snippet is provided. In 'Base64' mode, the string is Base64-encoded with a decode call.
Typical Use Cases
- Hiding a simple configuration string in JavaScript source code from casual viewers
- Generating Unicode escape sequences for strings in source code that a linter flags as non-ASCII
- Creating CTF challenge strings where the encoding is part of the puzzle
- Analyzing how JavaScript obfuscators represent strings to understand deobfuscation techniques
Step-by-step Guide
- Step 1: Enter the string you want to obfuscate in the input field.
- Step 2: Select the obfuscation method (char codes, Unicode escapes, hex escapes, XOR, Base64).
- Step 3: For XOR, enter a key string or generate a random one.
- Step 4: Copy the obfuscated output and optionally the decoder snippet.
Example
Input
Hello
Output
String.fromCharCode(72,101,108,108,111)
Tips & Notes
- Obfuscation is security through obscurity – it delays a determined attacker by minutes, not hours. For real secret protection, use server-side storage of secrets, not client-side obfuscation.
- Unicode escape sequences (\u00e9) are useful for embedding non-ASCII characters in source files that must remain ASCII-safe.
- XOR obfuscation with a short key is easily reversed by frequency analysis – use it only as a light deterrent, not as security.
Frequently Asked Questions
Can obfuscation protect API keys in frontend JavaScript?
No. Any secret embedded in client-side JavaScript can be recovered by anyone with browser DevTools. API keys and secrets must live on the server or be protected by CORS and rate limiting on the API side, not by client-side obfuscation.
What is the difference between obfuscation and encryption?
Obfuscation makes something harder to read at a glance but can be reversed without a key. Encryption uses a key; without the key, the original content is computationally infeasible to recover. Obfuscation is cosmetic; encryption is a real security control.
Are Unicode escape sequences equivalent to the original characters?
Yes, exactly. \u0048 is identical to 'H' in JavaScript, Python, and most languages. Unicode escape sequences are purely a source representation; the runtime sees the same character.
String Obfuscator
Obfuscate strings such as secrets, IBANs, or tokens — configurable with visible leading/trailing characters and a custom masking character.
Open Tool