Python Formatter

About This Tool

The Python Code Formatter beautifies Python source code by applying consistent indentation that aligns with PEP 8 — Python's official style guide. Paste code with irregular indentation, collapsed lines, or unknown formatting and get clean, readable output instantly. This is especially useful when reviewing code snippets from forums, documentation examples, or legacy scripts.

All formatting runs entirely in your browser — no Python code is sent to any server. Since Python uses significant whitespace, this tool focuses on block-level indentation using keywords like def, class, if, for, and while. For full PEP 8 compliance including line length, imports, and blank lines, use Black or autopep8 in your local environment.

How to Use

1. Paste your Python code into the Input Python area, or click Sample to load an example.
2. Choose your indent size: 2 spaces or 4 spaces (PEP 8 recommends 4).
3. Click Format to reformat the code.
4. Review the formatted output, then click Copy to copy it to your clipboard.

Use Cases

Data scientists pasting Python snippets from Jupyter notebooks or Stack Overflow answers want consistent indentation before integrating them into a project. Backend developers reviewing legacy code reformat it for readability before refactoring. Students learning Python use this tool to understand how indentation defines block structure. Developers working on shared machines or tablets use this as a quick formatter when their IDE is unavailable.

FAQ

• Is this the same as Black or autopep8? — No. Black and autopep8 perform full AST-aware formatting. This tool does keyword-based indentation reflow, which is faster and works without Python installed, but is less precise for complex expressions.
• Will it break my multi-line strings? — Multi-line strings (triple-quoted) and continuation lines may not format perfectly. Review the output before using it in production.
• Does it support Python 3 syntax? — Yes. Type hints, f-strings, walrus operator, and other Python 3 constructs are preserved as-is; only indentation is changed.
• Is my code sent to any server? — No. All processing happens in your browser using JavaScript. Your Python code never leaves your device.