mypy

Optional static typing for Python

mypy Permissive license MIT Active ★ 20,592 v2.3.0 released 2026-07-13

Install

mypy on PyPI

pip

pip install mypy

uv

uv add mypy

poetry

poetry add mypy

Package facts

License	MIT (permissive)
Python support	supports the current Python release (>=3.10)
Install friction	low — pure-Python wheel
Runtime dependencies	6 — typing_extensions, mypy_extensions, pathspec, tomli, librt, ast-serialize
Maintenance	actively maintained — 31 days since the last release
Last repo commit	2026-08-13
First released	2009-09-09
Popularity	one of the top 1,000 most-downloaded packages on PyPI (30-day window, as of 2026-08-13)
Known vulnerabilities	none known (OSV.dev, checked 2026-08-13)

Evidence: mypy-2.3.0-py3-none-any.whl

Development Status :: 5 - Production/StableEnvironment :: ConsoleIntended Audience :: DevelopersProgramming Language :: Python :: 3Programming Language :: Python :: 3.10Programming Language :: Python :: 3.11Programming Language :: Python :: 3.12Programming Language :: Python :: 3.13Programming Language :: Python :: 3.14Programming Language :: Python :: 3.15Topic :: Software DevelopmentTyping :: Typed

About mypy

from the package's own PyPI description — quoted content, verbatim

Mypy: Static Typing for Python

Stable Version (image) Downloads (image) Build Status (image) Documentation Status (image) Chat at https://gitter.im/python/typing (image) Checked with mypy (image) Code style: black (image) Linting: Ruff (image)

Got a...

Read as markdown · JSON record · Source repository · Homepage · Docs

AI interpretation — verify before relying

AI-generated interpretation of the package facts above; every digit, version, license, or vulnerability id it cites is grounded in the facts already shown on this page

Mypy is a static type checker for Python that detects type errors before runtime by analyzing type hints in your code, helping catch bugs without executing the program.

Low install friction with a pure-wheel distribution and six runtime dependencies. Actively maintained with a release 31 days ago and 20592 repository stars; last commit on 2026-08-13 confirms ongoing development.

MIT license permits unrestricted use, modification, and distribution with minimal restrictions, making it suitable for both open-source and commercial projects.

Usage

pip install mypy

# Create a typed Python file
echo 'def greet(name: str) -> str:
    return "Hello " + name' > example.py

# Run type checker
mypy example.py

Requires Python 3.10 or later (supports 3.10–3.15); mypy is distributed as a compiled binary by default but --no-binary flag installs interpreted version if needed.

Verdict: Mypy is a mature, actively maintained static type checker (MIT licensed, no known vulnerabilities) with low install friction and broad Python version support. It is a top-1000 PyPI package suitable for development workflows seeking gradual typing adoption and early bug detection.

Needs verification

Whether the compiled mypyc binary is available for all supported Python versions and platforms.
Performance characteristics and memory overhead for large codebases relative to project scale.
Specific performance improvement factor from mypyc compilation mentioned in documentation.

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