# black > A Python auto code formatter. > More information: . - Auto-format a file or entire directory: `black {{path/to/file_or_directory}}` - Format the code passed in as a string: `black -c "{{code}}"` - Output whether a file or a directory would have changes made to them if they were to be formatted: `black --check {{path/to/file_or_directory}}` - Output changes that would be made to a file or a directory without performing them (dry-run): `black --diff {{path/to/file_or_directory}}` - Auto-format a file or directory, emitting exclusively error messages to `stderr`: `black --quiet {{path/to/file_or_directory}}` - Auto-format a file or directory without replacing single quotes with double quotes (adoption helper, avoid using this for new projects): `black --skip-string-normalization {{path/to/file_or_directory}}`