Format
Rewrites your C++ with consistent braces, spacing, and indentation using clang-format. Turns cramped or messy code into clean, readable source.
Before
class A{int x;};Afterclass A {
int x;
};C++ Formatter and Beautifier
Paste cramped or messy C++ and get it back with consistent braces, spacing, and indentation. The formatter is clang-format, running in your browser, so your code stays on your device.
Indent
Style
Format uses clang-format. The style and indent options apply to Format.
Result
What a C++ formatter does
C++ gives you a lot of freedom over spacing and brace placement, and templates and long type names make it easy for code to get cramped. A formatter, also called a beautifier, rewrites the source with one consistent set of rules: braces in the same place, even indentation, and consistent spacing. This tool uses clang-format, a widely used C++ formatter, and changes only the layout, never what the program does.
Why use our C++ beautifier
- ·Free. No signup, no paywall, no limits.
- ·Runs in your browser. clang-format runs locally as WebAssembly, so your code is never uploaded.
- ·Real styles. Format to Google, LLVM, Mozilla, and other well-known C++ styles.
- ·Your house style. Choose 2 or 4 space indentation to match your project.
- ·Syntax highlighting. The editor colours keywords and types, and lets you collapse and expand blocks.
C++ formatter options
Style
Pick the base style clang-format follows: Google, LLVM, Mozilla, WebKit, and more. Each sets brace placement, spacing, and other rules to match a well-known C++ style.
Before
Google, LLVM, Mozilla...AfterYour chosen house styleIndent
Choose 2 or 4 spaces for each level of nesting, so the formatted C++ matches the style used in the rest of your project.
Before
2 spaces or 4 spacesAfterYour choice per levelWhen to format C++
A formatter helps whenever C++ source is hard to read or needs to match a shared style. These are the cases that come up most:
- ·Matching a project style. Reformat code to Google or LLVM before you commit it.
- ·Cleaning up pasted code. Clean up a snippet from a forum, a textbook, or a code generator.
- ·Reviewing a pull request. Make dense template code readable before you review or merge it.
- ·Learning C++. See how well-structured C++ is laid out while you are learning.
Learn more about C++
Once your C++ is formatted, these references explain the language and the formatter behind this tool:
- ·The C++ reference on cppreference.com documents the standard library and language.
- ·The Standard C++ Foundation is the home of the C++ language and its news.
- ·The clang-format style options explain every rule the base styles set.
Run clang-format on your own C++ code
This tool runs clang-format, the standard formatter for C++, compiled to run in your browser. The same styles work on your machine:
| To | Use |
|---|---|
| Format a file in place | clang-format -i main.cpp |
| Pick a base style | clang-format -i --style=Google main.cpp |
| Save a style for the project | clang-format --style=LLVM --dump-config > .clang-format |
| Format on save | The C/C++ extension in VS Code and CLion both use a .clang-format file if one is present |
When a .clang-format file is in your project folder, clang-format uses it automatically, so everyone on the team gets the same layout.
Related formatters
If you work across languages, these formatters run the same way, right in your browser:
Frequently asked questions
- What is a C++ formatter?
- A C++ formatter takes source code that has cramped or messy spacing and rewrites it with consistent braces, spacing, and indentation so it is easy to read. This tool uses clang-format, the same formatter built into many C++ toolchains, and does not change what your program does, only how the code is laid out.
- How do I format C++ code?
- Paste your C++ into the input box, pick a base style and indentation, then click Format. The clean version appears below. Click the copy button to copy it, or download it as a .cpp file.
- Does formatting change how my C++ program works?
- No. Formatting only changes whitespace, braces, and line breaks. The classes, templates, functions, and logic stay the same, so the program compiles and runs exactly as before.
- What are the style options?
- The style options are the base styles clang-format supports, such as Google, LLVM, Mozilla, WebKit, Chromium, Microsoft, and GNU. Each one sets a full set of rules for brace placement, spacing, and alignment. Pick the one that matches your project.
- Is this a C++ beautifier?
- Yes. Format and beautify mean the same thing here: taking messy C++ and laying it out cleanly with proper indentation and spacing. Some people call it a C++ beautifier, prettifier, or pretty printer.
- Is my C++ code kept private?
- Yes. The formatter is clang-format compiled to WebAssembly and runs entirely in your browser. Your code is never uploaded to a server or saved anywhere, so you can safely paste in code from a private project. Once the page has loaded you can even use it offline.