Python Formatter

Beautify and standardize Python 3 code with a fast, modern formatter whose style matches Black / PEP 8 conventions. Adjust indent width, quote style, line width, and magic trailing commas. Syntax errors are reported exactly, never silently reformatted. More code tools: Go Formatter | C/C++/C#/Java Formatter | Shell Script Formatter | Code Formatter (JS/TS/PHP/TOML).
All processing happens locally in your browser — your code is never uploaded to any server.
Input Python
Formatted Python
How to use: Paste your Python code in the left textarea and click Process (or just type — auto-process on input).
Behavior: Normalizes indentation, spaces around operators, comma spacing, quote style (when set), and line width. Magic trailing commas are respected by default (Black-style parenthesized continuation).
Syntax errors: Invalid Python is reported with the exact parse error instead of being silently mangled — fix the code and Process again.
Privacy: The formatter runs entirely inside your browser. Nothing is ever uploaded.
PEP 8, Black and line length

PEP 8 is Python’s official style guide: 4-space indents, snake_case names, and the 79-character line limit that dates from an era of narrow terminals. Black reformats everything to its own fixed opinions and refuses configuration; autopep8 only fixes what a linter flags and otherwise leaves your style alone.

Choose by blast radius — Black produces a large one-time diff but stable output forever, autopep8 is gentle but keeps whatever habits you already have.