flake8

Python code linter and style checker

TLDR

Check Python file

$ flake8 [file.py]

Check directory

$ flake8 [src/]

Show specific errors

$ flake8 --select=[E,W] [file.py]

Ignore specific errors

$ flake8 --ignore=[E501] [file.py]

Set max line length

$ flake8 --max-line-length=[120] [file.py]

flake8 is a Python linting tool combining PyFlakes, pycodestyle, and McCabe complexity checker. It finds programming errors, style issues, and overly complex code.The tool enforces PEP 8 style guidelines and catches common errors like undefined variables, unused imports, and syntax problems. Plugins extend checking for additional frameworks and patterns.flake8 integrates with editors, CI pipelines, and pre-commit hooks for automated code quality enforcement.

PARAMETERS

FILES

Python files or directories to check.

--select ERRORS

Check only specific error codes.

--ignore ERRORS

Ignore specific error codes.

--max-line-length N

Maximum line length (default 79).

--exclude PATTERNS

Exclude matching files/directories.

--config FILE

Configuration file.

--format FORMAT

Output format.

--help

Display help information.

CONFIGURATION

setup.cfg

Project-level flake8 configuration in the [flake8] section.

.flake8

Dedicated flake8 configuration file for project settings.

~/.config/flake8

User-level global configuration file.

INSTALL

sudo apk add py3-flake8

brew install flake8

CAVEATS

Strict defaults may require customization. Some checks overlap with other tools. Plugin ecosystem varies in quality.

HISTORY

flake8 was created by Tarek Ziadé to unify Python linting tools. It wraps multiple checkers under a single interface with consistent configuration and output.

RESOURCES

Source code · Documentation