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Asynchronous HTTP client/server framework for asyncio and Python
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Async http client/server framework

aiohttp logo

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Key Features

  • Supports both client and server side of HTTP protocol.
  • Supports both client and server Web-Sockets out-of-the-box and avoids Callback Hell.
  • Provides Web-server with middlewares and plugable routing.

Getting started


To get something from the web:

import aiohttp
import asyncio

async def main():

    async with aiohttp.ClientSession() as session:
        async with session.get('') as response:

            print("Status:", response.status)
            print("Content-type:", response.headers['content-type'])

            html = await response.text()
            print("Body:", html[:15], "...")

loop = asyncio.get_event_loop()

This prints:

Status: 200
Content-type: text/html; charset=utf-8
Body: <!doctype html> ...

Comming from requests ? Read why we need so many lines.


An example using a simple server:

# examples/
from aiohttp import web

async def handle(request):
    name = request.match_info.get('name', "Anonymous")
    text = "Hello, " + name
    return web.Response(text=text)

async def wshandle(request):
    ws = web.WebSocketResponse()
    await ws.prepare(request)

    async for msg in ws:
        if msg.type == web.WSMsgType.text:
            await ws.send_str("Hello, {}".format(
        elif msg.type == web.WSMsgType.binary:
            await ws.send_bytes(
        elif msg.type == web.WSMsgType.close:

    return ws

app = web.Application()
app.add_routes([web.get('/', handle),
                web.get('/echo', wshandle),
                web.get('/{name}', handle)])

if __name__ == '__main__':



External links

Feel free to make a Pull Request for adding your link to these pages!

Communication channels

aio-libs discourse group:

gitter chat

We support Stack Overflow. Please add aiohttp tag to your question there.


Optionally you may install the cChardet and aiodns libraries (highly recommended for sake of speed).


aiohttp is offered under the Apache 2 license.


The aiohttp community would like to thank Keepsafe ( for its support in the early days of the project.

Source code

The latest developer version is available in a GitHub repository:


If you are interested in efficiency, the AsyncIO community maintains a list of benchmarks on the official wiki:

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