black VS mypy

Compare black vs mypy and see what are their differences.

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black mypy
320 111
36,901 17,253
3.2% 1.5%
9.4 9.6
about 21 hours ago about 8 hours ago
Python Python
MIT License GNU General Public License v3.0 or later
The number of mentions indicates the total number of mentions that we've tracked plus the number of user suggested alternatives.
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.


Posts with mentions or reviews of black. We have used some of these posts to build our list of alternatives and similar projects. The last one was on 2024-02-15.
  • Uv: Python Packaging in Rust
    9 projects | | 15 Feb 2024
  • Let's meet Black: Python Code Formatting
    2 projects | | 7 Feb 2024
    In the realm of Python development, there is a multitude of code formatters that adhere to PEP 8 guidelines. Today, we will briefly discuss how to install and utilize black.
  • Show HN: Visualize the Entropy of a Codebase with a 3D Force-Directed Graph
    6 projects | | 31 Jan 2024
    Perfect, that worked, thank you!

    I thought this could be solved by changing the directory to src/ and then executing that command, but this didn't work.

    This also seems to be an issue with the web app, e.g. the repository for the formatter black is only one white dot

  • Introducing Flask-Muck: How To Build a Comprehensive Flask REST API in 5 Minutes
    3 projects | | 20 Dec 2023
  • Embracing Modern Python for Web Development
    12 projects | | 8 Dec 2023
    Ruff is not only much faster, but it is also very convenient to have an all-in-one solution that replaces multiple other widely used tools: Flake8 (linter), isort (imports sorting), Black (code formatter), autoflake, many Flake8 plugins and more. And it has drop-in parity with these tools, so it is really straightforward to migrate from them to Ruff.
  • Releasing my Python Project
    4 projects | | 26 Nov 2023
    1. LICENSE: This file contains information about the rights and permissions granted to users regarding the use, modification, distribution, and sharing of the software. I already had an MIT License in my project. 2. pyproject.toml: It is a configuration file typically used for specifying build requirements and backend build systems for Python projects. I was already using this file for Black code formatter configuration. 3. Used as a documentation file for your project, typically includes project overview, installation instructions and optionally, contribution instructions. 4. example_package_YOUR_USERNAME_HERE: One big change I had to face was restructuring my project, essentially packaging all files in this directory. The name of this directory should be what you want to name your package and shoud not conflict with any of the existing packages. Of course, since its a Python Package, it needs to have an 5. tests/: This is where you put all your unit and integration tests, I think its optional as not all projects will have tests. The rest of the project remains as is.
  • Lute v3 - installed software for learning foreign languages through reading
    2 projects | /r/flask | 15 Nov 2023
    using pylint and black ("the uncompromising code formatter")
  • Testing Python Code Using UnitTest
    3 projects | | 9 Nov 2023
    It was with this test that I made that I was able to test my parse_md function, previously called check_md_and_write, and locate a bug that I uncovered a last week. I noticed this bug when I was using the linter, Ruff, and formatter, Black, I set up for my project. If you're interested in reading about the linter and formatter I chose and the setup process you can read last week's blog. Essentially the problem was that I could not parse any Markdown in my program. I wasn't sure what the problem was, but I think it had something to do with when I refactored my code and tried to clean things up. Luckily, I still has the branches where I worked on improved the function to parse markdown and the refactoring branch. To make note of it, I made an issue for myself and specified which branches to take a look at.
  • FastAPI Production Setup Guide 🏁⚡️🚀
    6 projects | | 18 Oct 2023
    Whenever I start a new project I like to maintain quality standards and using automated quality tools makes it easy. Lets go ahead and install mypy for static type checking, black for formatting, and ruff for linting. Add these to the dev dependencies.
  • Django Code Formatting and Linting Made Easy: A Step-by-Step Pre-commit Hook Tutorial
    7 projects | | 4 Oct 2023
    Black is a Python code formatter that automatically formats Python code to comply with its style guide called PEP 8. PEP 8 is the official style guide for Python code, and it provides recommendations on how to format code for better readability and consistency.


Posts with mentions or reviews of mypy. We have used some of these posts to build our list of alternatives and similar projects. The last one was on 2024-02-13.
  • Polars – A bird's eye view of Polars
    4 projects | | 13 Feb 2024
    It's got type annotations and mypy has a discussion about it here as well:
  • Python 3.13 Gets a JIT
    11 projects | | 9 Jan 2024
    There is already an AOT compiler for Python: Nuitka[0]. But I don't think it's much faster.

    And then there is mypyc[1] which uses mypy's static type annotations but is only slightly faster.

    And various other compilers like Numba and Cython that work with specialized dialects of Python to achieve better results, but then it's not quite Python anymore.



  • Introducing Flask-Muck: How To Build a Comprehensive Flask REST API in 5 Minutes
    3 projects | | 20 Dec 2023
  • It's Time for a Change: Datetime.utcnow() Is Now Deprecated
    5 projects | | 19 Nov 2023
    It's funny you should say this.

    Reading this article prompted me to future-proof a program I maintain for fun that deals with time; it had one use of utcnow, which I fixed.

    And then I tripped over a runtime type problem in an unrelated area of the code, despite the code being green under "mypy --strict". (and "100% coverage" from tests, except this particular exception only occured in a "# pragma: no-cover" codepath so it wasn't actually covered)

    It turns out that because of some core decisions about how datetime objects work, ` <` type-checks but gives a TypeError at runtime. Oops. (cause discussed at length in but without action for 3 years)

    One solution is apparently to use `datetype` for type annotations (while continuing to use `datetime` objects at runtime):

  • What's New in Python 3.12
    5 projects | | 18 Oct 2023
    PEP 695 is great. I've been using mypy every day at work in last couple years or so with very strict parameters (no any type etc) and I have experience writing real life programs with Rust, Agda, and some Haskell before, so I'm familiar with strict type systems. I'm sure many will disagree with me but these are my very honest opinions as a professional who uses Python types every day:

    * Some types are better than no types. I love Python types, and I consider them required. Even if they're not type-checked they're better than no types. If they're type-checked it's even better. If things are typed properly (no any etc) and type-checked that's even better. And so on...

    * Having said this, Python's type system as checked by mypy feels like a toy type system. It's very easy to fool it, and you need to be careful so that type-checking actually fails badly formed programs.

    * The biggest issue I face are exceptions. Community discussed this many times [1] [2] and the overall consensus is to not check exceptions. I personally disagree as if you have a Python program that's meticulously typed and type-checked exceptions still cause bad states and since Python code uses exceptions liberally, it's pretty easy to accidentally go to a bad state. E.g. in the linked github issue JukkaL (developer) claims checking things like "KeyError" will create too many false positives, I strongly disagree. If a function can realistically raise a "KeyError" the program should be properly written to accept this at some level otherwise something that returns type T but 0.01% of the time raises "KeyError" should actually be typed "Raises[T, KeyError]".

    * PEP 695 will help because typing things particularly is very helpful. Often you want to pass bunch of Ts around but since this is impractical some devs resort to passing "dict[str, Any]"s around and thus things type-check but you still get "KeyError" left and right. It's better to have "SomeStructure[T]" types with "T" as your custom data type (whether dataclass, or pydantic, or traditional class) so that type system has more opportunities to reject bad programs.

    * Overall, I'm personally very optimistic about the future of types in Python!


  • Mypy 1.6 Released
    5 projects | | 17 Oct 2023
  • Ask HN: Why are all of the best back end web frameworks dynamically typed?
    4 projects | | 5 Oct 2023
    You probably already know but you can add type hints and then check for consistency with in python.

    Modern Python with things like + mypy + Ruff for linting can get pretty good results.

    I found typed dataclasses ( in python using mypy to give me really high confidence when building data representations.

  • Sharing Saturday #472
    7 projects | /r/roguelikedev | 23 Jun 2023
    The in-progress tutorial is here in the official documentation. It sucks that I can never seem to make quick progress on this. Trying to do something clever with Protocols ended up with me making a pull request on the Mypy project for something that likely wasn't critical after all.
  • Writing Python like it's Rust
    10 projects | | 21 May 2023
    I'm also 100% convinced most people who use mypy don't realize the myriad ways it just silently stopps typing things or just silently crashes with a 0 exit code. Even if you configure it to warn untyped functions etc. It will still just not work properly in some of circumstances and you will literally never know until you debug a bug that just happened to trigger it. There are over 1.4k open but tickets it's such a broken piece of software:

    The involvement of Guido in mypy is such a tragedy.

  • Authentication system using Python (Django) and SvelteKit
    7 projects | | 16 May 2023
    The backend service was built using Django with PostgreSQL database, Redis for session storage, and AWS S3 for file storage. The APIs were built without the use of external REST API frameworks such as Django REST framework. Data serialization and JSON responses were manually handled. Most of the views were made asynchronous. For testing, pytest and its ecosystem were heavily used. Mypy, Pylint and others were used for Static analysis. GitHub Actions were used for automated testing, coverage report and static analysis.

What are some alternatives?

When comparing black and mypy you can also consider the following projects:

autopep8 - A tool that automatically formats Python code to conform to the PEP 8 style guide.

pyright - Static Type Checker for Python

prettier - Prettier is an opinionated code formatter.

yapf - A formatter for Python files

Pylint - It's not just a linter that annoys you!

ruff - An extremely fast Python linter and code formatter, written in Rust.

isort - A Python utility / library to sort imports.

autoflake - Removes unused imports and unused variables as reported by pyflakes

Flake8 - flake8 is a python tool that glues together pycodestyle, pyflakes, mccabe, and third-party plugins to check the style and quality of some python code.

pyre-check - Performant type-checking for python.

pycodestyle - Simple Python style checker in one Python file