Python Formatter Online

Format Python Code to PEP 8 Standards — Free

A Python formatter automatically applies PEP 8 style guidelines to your code — fixing indentation, adding proper spacing around operators, and ensuring consistent formatting. This tool links to our Python code tools to help you write cleaner code.

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What is PEP 8?

PEP 8 is Python's official style guide. It covers naming conventions, indentation (4 spaces), line length (79 chars max), import ordering, and whitespace usage. Following PEP 8 makes code more readable and maintainable.

# Bad (not PEP 8)

def myFunction( x,y):

return x+y

# Good (PEP 8)

def my_function(x, y):

return x + y

Popular Python Formatters

Black

The "uncompromising" formatter — no configuration needed

pip install black && black .

autopep8

Fixes PEP 8 violations, more conservative than Black

pip install autopep8 && autopep8 --in-place file.py

isort

Sorts imports alphabetically and by section

pip install isort && isort .

ruff

Extremely fast formatter written in Rust

pip install ruff && ruff format .

Key PEP 8 Rules

✓

Indentation: Use 4 spaces per indentation level (not tabs)

✓

Max Line Length: 79 characters for code, 72 for docstrings

✓

Imports: One import per line, grouped: stdlib, third-party, local

✓

Spaces: Spaces around operators: x = 1 + 2 (not x=1+2)

✓

Blank Lines: 2 blank lines before top-level functions/classes

✓

Naming: snake_case for functions/variables, PascalCase for classes

✓

Docstrings: Triple-quoted strings for all public modules/functions/classes

FAQ

Which Python formatter should I use?

Black is the most popular — it's opinionated and fast. autopep8 is lighter and follows PEP 8 strictly. isort handles import sorting. For VS Code, install the Python extension with Black as the formatter.

How do I run a Python formatter locally?

Install Black: pip install black, then run: black your_file.py. For autopep8: pip install autopep8, then: autopep8 --in-place your_file.py

Does Python formatting affect performance?

No. Formatting only changes whitespace and style — the compiled bytecode is identical. Formatting is purely for human readability.

How to Use

Enter or paste your data in the input field
Configure any options if available
Click the action button to process
Copy the result to your clipboard

Use Cases

Development and debugging workflows
Data format conversion
Code generation and formatting
Quick calculations and validation

FAQ

Is this Python Formatter tool free to use?

Yes, the Python Formatter tool is completely free. No registration or payment required.

Is my data secure?

Absolutely. All processing happens client-side in your browser. Your data never leaves your device or is sent to any server.

What formats does the Python Formatter tool support?

The tool supports all standard formats for data processing. Check the tool interface for specific format options.