A Python tool to check ASS subtitles for common mistakes and errors.


pip install --user ass-lint

To do:

  • Split some of the big classes into separate files
  • Add human readable and numeric codes to each check
  • Allow disabling each checks via command line and via inline comments
  • Allow setting the language via command line
  • Allow setting the fonts directory via command line
  • Provide documentation for some more exotic checks such as the fonts check


# Clone the repository:
git clone
cd ass_lint

# Install to a local venv:
poetry install

# Install pre-commit hooks:
poetry run pre-commit install

# Enter the venv:
poetry shell

This project uses for packaging, install instructions at poetry#installation


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