About

Posting raw code on MyBB forums produces a monochrome wall of text. Readers lose context. Bugs hide in plain sight. This converter tokenizes your source code using a language-aware lexer and wraps each token in the appropriate [color] BBCode tag. It applies distinct colors to keywords, strings, numbers, comments, operators, and identifiers. The output pastes directly into any MyBB-compatible editor. The tokenizer handles single-line comments (//, #), block comments (/* */), nested strings with escape sequences, and language-specific keyword sets for 12 languages including JavaScript, Python, Java, C, PHP, SQL, and Go.

Limitations: this tool performs lexical analysis only. It does not build an AST, so context-dependent highlighting (e.g., distinguishing a function name from a variable) is approximate. Multi-line template literals and heredocs may tokenize imperfectly. For most forum posts under 500 lines, accuracy exceeds 95% of tokens. Pro tip: choose the correct language from the dropdown. The generic fallback applies C-family heuristics which miscolor Python decorators and Ruby symbols.

Formulas

The converter operates as a deterministic finite tokenizer. For a given input string S of length n, the algorithm scans left to right at position i = 0 to n − 1. At each position it attempts to match the longest token using ordered priority rules:

T(i) = match(S, i, R_lang)

Where R_lang is the ordered ruleset for the selected language. Each rule is a pair (pattern, tokenType). The first matching pattern wins. The output function O maps each token to BBCode:

O(token) = [color=C(token.type)] ⋅ token.value ⋅ [/color]

Where C is the color lookup table mapping token types to hex values. Whitespace tokens pass through unmodified. The final output is the concatenation of all O(T_i) values, optionally wrapped in [font=Courier New]...[/font] for monospace rendering. Time complexity is O(n ⋅ k) where k is the number of rules per language (typically 8 - 15).

Reference Data

Token Type	Color	Hex Code	Example	MyBB Output
Keyword	■ Medium Slate Blue	#7B68EE	function, if, class	[color=#7B68EE]function[/color]
String	■ Sea Green	#2E8B57	"hello"	[color=#2E8B57]"hello"[/color]
Number	■ Chocolate	#D2691E	42, 3.14	[color=#D2691E]42[/color]
Comment	■ Gray	#808080	// todo	[color=#808080]// todo[/color]
Operator	■ Indian Red	#CD5C5C	+, =, <	[color=#CD5C5C]+[/color]
Punctuation	■ Dark Gray	#555555	( ) { } [ ] ; ,	[color=#555555]{[/color]
Built-in / Type	■ Dodger Blue	#1E90FF	console, int, String	[color=#1E90FF]console[/color]
Constant / Boolean	■ Dark Goldenrod	#B8860B	TRUE, NULL, None	[color=#B8860B]true[/color]
Identifier	■ Near Black	#333333	myVar, count, getData	[color=#333333]myVar[/color]
Decorator / Annotation	■ Purple	#AA22FF	@Override, @property	[color=#AA22FF]@Override[/color]
Preprocessor	■ Lavender	#BC6EC5	#include, #define	[color=#BC6EC5]#include[/color]
Regex Literal	■ Rose	#DD4488	/[a-z]+/gi	[color=#DD4488]/[a-z]+/gi[/color]
Whitespace	-	-	Spaces, tabs, newlines	(preserved as-is)

Frequently Asked Questions

The tokenizer uses a per-language keyword set. If you select JavaScript but paste Python, words like "def" and "elif" will render as plain identifiers (color #333333) instead of keywords (#7B68EE). Always select the correct language. The "Auto-detect" option uses heuristics (shebang lines, common patterns) but cannot guarantee accuracy for short snippets under 5 lines.

Square brackets [ and ] inside your code are not escaped because MyBB's [code] tag treats content literally. However, if you use the [font] wrapper mode instead of [code], brackets in your source will be interpreted as BBCode tags. In that case, the converter does NOT auto-escape them. You must manually replace [ with [ if using font-wrapper mode with bracket-heavy code (e.g., array access in C).

Yes. The color table is defined in the converter's configuration. Click the gear icon to open color settings. Each of the 10 token types has an editable hex value. Changes persist in localStorage. The defaults are optimized for white/light-gray forum backgrounds. For dark themes, increase lightness values: try #9B88FF for keywords, #50D080 for strings, and #F0A050 for numbers.

The tokenizer processes code synchronously in the browser. For snippets under 2000 lines (roughly 80 KB), conversion is near-instant (under 50 ms). Between 2000 and 10000 lines, expect 200-500 ms. Beyond 10000 lines, the browser may briefly freeze. MyBB itself typically limits post length to 10000-65535 characters depending on forum configuration. The BBCode output is 3-5× larger than the input due to color tags, so a 200-line snippet may produce 15 KB of BBCode.

MyBB's [code] tag strips all BBCode inside it, rendering everything as plain monochrome text. To preserve [color] tags, you must use [font=Courier New][/font] as the outer wrapper. The trade-off: [font] does not provide a scrollable code box or line numbers. Some forums have custom plugins that allow colored [code] blocks. Check your forum's capabilities. The converter defaults to [font] wrapping for compatibility.

Single and double-quoted strings with backslash escapes are fully supported across all languages. Python triple-quoted strings (''' and """) are recognized. JavaScript template literals (backtick strings) are tokenized as strings but embedded ${expressions} inside them are NOT separately highlighted - the entire literal including interpolations is colored as a string. This is a known limitation of lexer-only analysis.