Free C++ Formatter & Validator

Format, beautify, and validate your C++ code. Check for syntax errors and get clean, readable code following standard conventions.

Input C++ Code

C++ Standard:

Results

Status Awaiting input

Formatted C++ Code

// Formatted C++ code will appear here...

How To Use C++ Formatter & Validator

📝 Step 1: Enter C++ Code

Paste your C++ source code in the input area. Supports multiple functions and classes.

⚙️ Step 2: Choose C++ Standard

Select your target C++ version (C++11 to C++20) for appropriate formatting rules.

🔧 Step 3: Format or Validate

Click "Format Code" to beautify with proper indentation. Click "Validate Code" to check for syntax errors.

📋 Step 4: Copy or Download

Use the "Copy" button to copy formatted code to clipboard, or "Download" to save as .cpp file.

💡 Pro Tips

  • Use the Sample button to load an example class
  • Validation checks for: missing semicolons, unmatched braces/parentheses
  • Formatting preserves comments and preprocessor directives
  • Works with complex templates and STL code

🔍 Example

// Before formatting: class MyClass{public:MyClass(){value=0;}void setValue(int v){value=v;}private:int value;}; // After formatting: class MyClass { public: MyClass() { value = 0; } void setValue(int v) { value = v; } private: int value; };

Frequently Asked Questions

What C++ standards are supported? ▼
We support C++11, C++14, C++17, and C++20. Each standard has specific formatting conventions for features like auto, lambdas, and structured bindings.
Does it validate all C++ syntax? ▼
The validator checks for common syntax errors including: missing semicolons, unmatched braces/parentheses, and basic structure. It's designed for standard C++ but may not catch template metaprogramming errors.
What formatting options are available? ▼
The formatter adds proper indentation, line breaks after braces, aligns class members, and standardizes spacing. It follows common C++ style guides like Google's or LLVM's.
Can I format multiple classes/functions? ▼
Yes! The tool handles entire files with multiple classes, functions, and namespaces. Each construct is formatted independently while maintaining overall file structure.
Is my C++ code secure? ▼
Absolutely. Formatting happens entirely in your browser. Validation is done both client-side and server-side, but your actual code is never stored or logged.
What are common C++ errors it detects? ▼
Common errors include: missing semicolons, unmatched braces/parentheses, missing main() function, and incorrect namespace syntax.
Does it work with templates? ▼
Yes, basic template syntax is supported. The formatter will properly indent template declarations and specializations.
How accurate is the validation? ▼
The validator catches most syntax errors but won't catch semantic errors like type mismatches or undefined identifiers. It's great for quick syntax checking and formatting.