autopep8

Automatically format Python code to PEP 8 style

TLDR

Format Python file

$ autopep8 --in-place [file.py]

Format with aggressive fixes

$ autopep8 --in-place --aggressive --aggressive [file.py]

Show diff instead of modifying

$ autopep8 --diff [file.py]

Format recursively

$ autopep8 --in-place --recursive [directory/]

Select specific fixes

$ autopep8 --select=[E501,W293] --in-place [file.py]

SYNOPSIS

autopep8 [--in-place] [--aggressive] [options] files

autopep8 automatically formats Python code to conform to PEP 8 style guide. It fixes issues like whitespace, indentation, and line length while preserving code semantics.
The tool integrates with editors and CI pipelines to enforce consistent Python style.

PARAMETERS

-i, --in-place

Modify files in place

-d, --diff

Print diff instead of modifying

-r, --recursive

Process directories recursively

-a, --aggressive

More aggressive fixes (repeatable for more aggression)

--select=errors

Fix only specified errors

--ignore=errors

Ignore specified errors

--max-line-length=n

Maximum line length (default: 79)

--range start end

Only fix lines in range

--exclude patterns

Exclude file patterns

CONFIGURATION

setup.cfg

Project-level configuration under `[pycodestyle]` section.

pyproject.toml

Project-level configuration under `[tool.autopep8]` section.

~/.config/pycodestyle

User-level default configuration for pycodestyle rules.

ERROR CODES

Based on PEP 8:
- E: Errors
- W: Warnings
- Examples: E501 (line too long), W291 (trailing whitespace)

CAVEATS

May conflict with other formatters like black. Aggressive mode can change code logic in rare cases. Review changes before committing. Black is now more popular for opinionated formatting.

HISTORY

autopep8 was created by Hideo Hattori to provide automatic PEP 8 compliance, released around 2010.