Instantly format, beautify, and validate Python code. PEP 8 compliant with syntax highlighting, indentation fixing, and real-time error detection — no install needed.
A Python formatter (also known as a Python beautifier) automatically restructures Python source code to comply with PEP 8 — Python's official style guide authored by Guido van Rossum. Consistently formatted Python code is easier to read, review, and maintain, especially in collaborative environments. Key PEP 8 rules include: use 4 spaces per indentation level (never tabs mixed with spaces), limit lines to 79 characters, surround top-level functions and classes with two blank lines, use spaces around operators and after commas, and place imports on separate lines. Tools like Black, autopep8, and YAPF automate this process. Our free online Python formatter applies these rules instantly — fix inconsistent indentation, normalise quote style, sort imports (isort-style), and detect mixed tab/space errors. Whether you're a beginner learning Python syntax or a senior developer reviewing pull requests, a well-formatted codebase reduces cognitive load and improves code quality across the entire team.
Professional-grade Python beautifier built for developers, data scientists, and educators.
Automatically enforce Python's official PEP 8 style guide including indentation, line length, blank lines, and import ordering rules.
Color-coded output for keywords, strings, functions, classes, decorators, comments, and built-in functions — just like your IDE.
Get instant stats: function count, class count, import count, line count, complexity indicators, and style compliance percentage.
Auto-sort imports isort-style: standard library, third-party, local imports — each group separated by a blank line.
Standardise all string literals to single or double quotes (your choice) across the entire file, matching Black or your team style.
Your Python code is never uploaded anywhere. All formatting runs entirely in-browser — safe for proprietary or sensitive code.
Detects common Python errors as you type: mixed indentation, unclosed brackets, unmatched quotes, and invalid syntax patterns.
Upload any .py file, format it, and download the beautified result. Perfect for bulk reformatting legacy scripts.
Optionally add basic docstring stubs to functions and classes without existing documentation — jumpstart your documentation workflow.
No downloads, no accounts — just paste, format, and copy.
Paste raw Python code into the input editor, or upload a .py file from your local device.
Set indentation (PEP 8 = 4 spaces), max line length, quote style, and toggle features like import sorting.
Click "Format Python" to beautify. Review color-coded output and check the analysis panel for insights.
Copy the formatted code to clipboard or download the .py file — ready for your editor, GitHub, or docs.
Common questions about Python formatting, PEP 8, and our online beautifier tool.
PEP 8 is Python's official style guide that defines conventions for writing readable Python code. Consistent formatting makes code easier to review in pull requests, reduces bugs from indentation errors, and ensures your code follows the conventions expected by the Python community and popular frameworks like Django and Flask.
Yes. The formatter handles modern Python 3 syntax including f-strings, type annotations, walrus operator (:=), match statements (Python 3.10+), dataclasses, async/await syntax, and decorator stacking. Python 2 legacy code is also supported.
Black is an opinionated formatter with minimal config (88-char lines, double quotes). autopep8 applies only the PEP 8 fixes needed, preserving your original style where possible. YAPF (Yet Another Python Formatter) uses a full reformatting algorithm for the most algorithmically optimal layout. Our tool applies PEP 8 rules with configurable options similar to autopep8 + Black.
In Python 3, mixing tabs and spaces for indentation raises a TabError at runtime. Python 2 was more lenient, but PEP 8 explicitly forbids mixing. Our formatter detects mixed indentation and converts everything to your chosen style consistently.
Yes! You can copy individual cell contents from a Jupyter Notebook, paste into this formatter, and copy the formatted code back. For full notebook formatting, consider using nbqa or black[jupyter] in your local environment alongside this tool for quick edits.
100% free with no registration, no rate limits, and no file size caps (within browser memory). Since everything runs client-side, you can format large Python files offline too — just keep the page open.
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