multidict

multidict implementation

multidict Permissive license Apache License 2.0 Active ★ 491 v6.7.1 released 2026-01-26

Install

multidict on PyPI

pip

pip install multidict

uv

uv add multidict

poetry

poetry add multidict

Package facts

License	Apache License 2.0 (permissive)
Python support	supports the current Python release (>=3.9)
Install friction	low — pure-Python wheel
Runtime dependencies	1 — typing-extensions
Maintenance	actively maintained — 199 days since the last release
Last repo commit	2026-08-11
First released	2016-02-19
Popularity	one of the 100 most-downloaded packages on PyPI (30-day window, as of 2026-08-13)
Known vulnerabilities	none known (OSV.dev, checked 2026-08-13)

Evidence: multidict-6.7.1-py3-none-any.whl

Development Status :: 5 - Production/StableIntended Audience :: DevelopersProgramming Language :: PythonProgramming 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 :: 3.9

About multidict

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

========= multidict =========

.. image:: https://github.com/aio-libs/multidict/actions/workflows/ci-cd.yml/badge.svg :target: https://github.com/aio-libs/multidict/actions :alt: GitHub status for master branch

.. image:: https://codecov.io/gh/aio-libs/multidict/branch/master/graph/badge.svg?flag=pytest :target: https://codecov.io/gh/aio-libs/multidict?flags[]=pytest :alt: Coverage metrics

.. image:: https://img.shields.io/pypi/v/multidict.svg :target: https://pypi.org/project/multidict :alt: PyPI

.. image:: https://readthedocs.org/projects/multidict/badge/?version=latest :target: https://multidict.aio-libs.org :alt: Read The Docs build status badge

.. image:: https://img.shields.io/endpoint?url=https://codspeed.io/badge.json :target: https://codspeed.io/aio-libs/multidict :alt: CodSpeed

.. image:: https://img.shields.io/pypi/pyversions/multidict.svg :target: https://pypi.org/project/multidict :alt: Python versions

.. image:: https://img.shields.io/matrix/aio-libs:matrix.org?label=Discuss%20on%20Matrix%20at%20%23aio-libs%3Amatrix.org&logo=matrix&server_fqdn=matrix.org&style=flat :target: https://matrix.to/#/%23aio-libs:matrix.org...

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

Multidict provides dict-like containers that allow multiple values per key while preserving insertion order, designed for HTTP headers and URL query strings where keys naturally repeat.

Low friction: pure Python wheel available, single lightweight runtime dependency (typing-extensions), and active maintenance with recent commits. C extensions are optional but recommended for performance.

Apache License 2.0 is permissive; you may use, modify, and distribute multidict freely in commercial and private projects provided you include the license notice.

Usage

pip install multidict
from multidict import MultiDict
md = MultiDict([('key', 'value1'), ('key', 'value2')])
print(md.getall('key'))  # ['value1', 'value2']

Requires Python 3.9 or later. C compiler needed only if installing from source on unsupported platforms; set MULTIDICT_NO_EXTENSIONS=1 to skip compilation.

Verdict: Multidict is a stable, actively maintained top-100 package with no known vulnerabilities, permissive licensing, and low install friction. It is production-ready for handling multi-valued dictionary use cases, though the pure Python fallback is significantly slower than the optional C extensions.

Needs verification

Whether C extension compilation succeeds reliably on all target platforms when not explicitly disabled
Performance characteristics of the pure Python implementation for your specific use case relative to the 20-50x slowdown mentioned

dict with multiple values per keyhttp headers data structureurl query string parsingcase-insensitive dictionarymultidict implementationrepeated keys containermutable mapping with duplicates