---
id: sniffio
version: "1.3.1"
license: MIT OR Apache-2.0
license_treatment: permissive
maintenance: active
---

# sniffio — Sniff out which async library your code is running under

License: permissive · Maintenance: active · Popularity: top 100 on PyPI

## Install

pip install sniffio
uv add sniffio
poetry add sniffio

## Description

.. image:: https://img.shields.io/badge/chat-join%20now-blue.svg
   :target: https://gitter.im/python-trio/general
   :alt: Join chatroom

.. image:: https://img.shields.io/badge/docs-read%20now-blue.svg
   :target: https://sniffio.readthedocs.io/en/latest/?badge=latest
   :alt: Documentation Status

.. image:: https://img.shields.io/pypi/v/sniffio.svg
   :target: https://pypi.org/project/sniffio
   :alt: Latest PyPi version
   
.. image:: https://img.shields.io/conda/vn/conda-forge/sniffio.svg
   :target: https://anaconda.org/conda-forge/sniffio 
   :alt: Latest conda-forge version   

.. image:: https://travis-ci.org/python-trio/sniffio.svg?branch=master
   :target: https://travis-ci.org/python-trio/sniffio
   :alt: Automated test status

.. image:: https://codecov.io/gh/python-trio/sniffio/branch/master/graph/badge.svg
   :target: https://codecov.io/gh/python-trio/sniffio
   :alt: Test coverage

=================================================================
sniffio: Sniff out which async library your code is running under
=================================================================

You're writing a library. You've decided to be ambitious,...

## AI interpretation — verify before relying

Detects which async library your code is currently running under, enabling libraries to support multiple async frameworks with a single codebase.

Verdict: A lightweight, well-maintained utility for multi-async-framework libraries. Zero dependencies, permissive dual licensing, active development, and no known vulnerabilities make it a low-risk addition to async codebases that need runtime library detection.

[View on SkillFed](https://skillfed.io/packages/sniffio) · [View on PyPI](https://pypi.org/project/sniffio/)