Black vs Ruff
Which should you use? A side-by-side look at what each one does, who it suits, what it costs, how hard it is to set up, and where each falls short.
Open source · MIT
A Python code formatter that rewrites your files to one consistent style with little configuration.
Open source · MIT
A very fast Python linter and code formatter, written in Rust.
The short answer
Choose Black if you need…
- Python developers who want formatting handled automatically
- Teams that want every project member's code to look the same
- Projects that already use pre-commit hooks or CI checks
- People who prefer not to debate style rules
Choose Ruff if you need…
- Python developers who want one tool for linting and formatting
- Teams with large Python codebases where slow checks are a problem
- People running checks in a pre-commit hook or editor on save
- Projects that already use pyproject.toml for configuration
Side-by-side
| Black | Ruff | |
|---|---|---|
| Type | Dev tool | CLI |
| Price | Free and open source | Free and open source |
| Licence | MIT | MIT |
| GitHub stars | 42.1k | 50.4k |
| Setup difficulty | Beginner | Beginner |
| How you get it | Install with a package manager | Install with a package manager |
| Main language | Python | Rust |
| Last code update | 4 days ago | 4 days ago |
What each one is
Black
Black is a command-line tool that automatically rewrites Python code into a consistent layout, so you stop spending time on spacing, line breaks, and quote style. It is opinionated and has few settings by design, so teams and projects end up looking alike. People use it to keep code reviews focused on logic rather than formatting.
Ruff
Ruff checks Python code for style problems and likely bugs, and can automatically format code and fix some errors. It is a single command-line tool that aims to replace several older Python tools such as Flake8, Black, and isort. The README says it is much faster than those tools, and it is installed through pip, uv, or pipx.
Best for
Black
- Python developers who want formatting handled automatically
- Teams that want every project member's code to look the same
- Projects that already use pre-commit hooks or CI checks
- People who prefer not to debate style rules
Ruff
- Python developers who want one tool for linting and formatting
- Teams with large Python codebases where slow checks are a problem
- People running checks in a pre-commit hook or editor on save
- Projects that already use pyproject.toml for configuration
Strengths
Black
- The README describes it as producing the smallest diffs possible, which makes code review easier
- Few configuration options are needed, and the README says the defaults are intended to work for most projects
- Documented stability policy means large style changes are not expected going forward
Ruff
- The README reports speeds of 10-100x over Flake8 and Black, with testimonials citing larger gains
- Combines linting, formatting, and import sorting behind one interface
- Supports hierarchical configuration for monorepos
Not ideal for
Black
- Anyone who wants fine-grained control over formatting choices, since the README says style options are deliberately limited
- Projects that need to run on Python versions older than 3.10, since the README says Black requires Python 3.10+ to run
Ruff
- Non-Python projects, since it only handles Python code
- People who need to keep using specific Flake8 plugins not covered by its rules (the README says it re-implements many popular ones, not all)
- Users who want a tool with no configuration decisions to learn; it has over 900 rules to choose from
Trade-offs
Black
- Its opinionated style means you cannot tune many formatting details
- The README notes it reformats files in place, so you should use version control before running it on existing code
Ruff
- Speed figures and testimonials come from the project and its users, not independent benchmarks
- Rule coverage is broad but may not match every plugin or edge case of the tools it replaces
- Version is under 1.0 (0.17.3), so behavior may change between releases
Getting started
Ruff
Install with uv (recommended)
uv tool install ruff@latestInstall with pip
pip install ruffFrequently asked questions
What is the difference between Black and Ruff?
Black: A Python code formatter that rewrites your files to one consistent style with little configuration. Ruff: A very fast Python linter and code formatter, written in Rust. Black suits python developers who want formatting handled automatically, while Ruff suits python developers who want one tool for linting and formatting.
Are Black and Ruff free?
Black: Free and open source. Ruff: Free and open source.
Is Black or Ruff more popular?
Ruff has more GitHub stars (50.4k) than Black (42.1k). Popularity isn't the same as fit — check which one matches your use case above.
What are other alternatives to Black and Ruff?
Other options people compare them with include Prettier, Gitingest, ast-grep.
Keep comparing
Built from our catalogue entries for both products: open-source details come from each project's README (AI-assisted, refreshed weekly) and GitHub data; AI-tool details are editorial. Spotted something wrong? Let us know from either product's page.