curl_cffi

Documentation

Python binding for curl-impersonate fork
via cffi. For commercial support, visit impersonate.pro.

Unlike other pure python http clients like httpx or requests, curl_cffi can
impersonate browsers’ TLS/JA3 and HTTP/2 fingerprints. If you are blocked by some
website for no obvious reason, you can give curl_cffi a try.

Python 3.9 is the minimum supported version since v0.10.

Sponsors

Maintenance of this project is made possible by all the contributors and sponsors. If you’d like to sponsor this project and have your avatar or company logo appear below click here. 💖

---

Scrape Google and other search engines from SerpApi’s fast, easy, and complete API. 0.66s average response time (≤ 0.5s for Ludicrous Speed Max accounts), 99.95% SLAs, pay for successful responses only.

---

Bypass Cloudflare with API

Yescaptcha is a proxy service that bypasses Cloudflare and uses the API interface to
obtain verified cookies (e.g. cf_clearance). Click here
to register: https://yescaptcha.com/i/stfnIO

---

Easy Captcha Bypass for Scraping

CapSolver
is an AI-powered tool that easily bypasses Captchas, allowing uninterrupted access to
public data. It supports a variety of Captchas and works seamlessly with curl_cffi,
Puppeteer, Playwright, and more. Fast, reliable, and cost-effective. Plus, curl_cffi
users can use the code “CURL” to get an extra 6% balance! and register here.

---

Features

• Supports JA3/TLS and http2 fingerprints impersonation, including recent browsers and custome fingerprints.
• Much faster than requests/httpx, on par with aiohttp/pycurl, see benchmarks.
• Mimics requests API, no need to learn another one.
• Pre-compiled, so you don’t have to compile on your machine.
• Supports asyncio with proxy rotation on each request.
• Supports http 2.0, which requests does not.
• Supports websocket.

	requests	aiohttp	httpx	pycurl	curl_cffi
http/2	❌	❌	✅	✅	✅
http/3	❌	❌	❌	☑️1	✅2
sync	✅	❌	✅	✅	✅
async	❌	✅	✅	❌	✅
websocket	❌	✅	❌	❌	✅
fingerprints	❌	❌	❌	❌	✅
speed	🐇	🐇🐇	🐇	🐇🐇	🐇🐇

Notes:

1. For pycurl, you need a http/3 enabled libcurl to make it work, while curl_cffi packages libcurl-impersonate inside Python wheels.
2. Since v0.11.0b1.

Install

pip install curl_cffi --upgrade

This should work on Linux, macOS and Windows out of the box.
If it does not work on you platform, you may need to compile and install curl-impersonate
first and set some environment variables like LD_LIBRARY_PATH.

To install beta releases:

pip install curl_cffi --upgrade --pre

To install unstable version from GitHub:

git clone https://github.com/lexiforest/curl_cffi/
cd curl_cffi
make preprocess
pip install .

Usage

curl_cffi comes with a low-level curl API and a high-level requests-like API.

requests-like

v0.9:

from curl_cffi import requests

r = requests.get("https://tls.browserleaks.com/json", impersonate="chrome")

v0.10:

import curl_cffi

# Notice the impersonate parameter
r = curl_cffi.get("https://tls.browserleaks.com/json", impersonate="chrome")

print(r.json())
# output: {..., "ja3n_hash": "aa56c057ad164ec4fdcb7a5a283be9fc", ...}
# the js3n fingerprint should be the same as target browser

# To keep using the latest browser version as `curl_cffi` updates,
# simply set impersonate="chrome" without specifying a version.
# Other similar values are: "safari" and "safari_ios"
r = curl_cffi.get("https://tls.browserleaks.com/json", impersonate="chrome")

# Randomly choose a browser version based on current market share in real world
# from: https://caniuse.com/usage-table
# NOTE: this is a pro feature.
r = curl_cffi.get("https://example.com", impersonate="realworld")

# To pin a specific version, use version numbers together.
r = curl_cffi.get("https://tls.browserleaks.com/json", impersonate="chrome124")

# To impersonate other than browsers, bring your own ja3/akamai strings
# See examples directory for details.
r = curl_cffi.get("https://tls.browserleaks.com/json", ja3=..., akamai=...)

# http/socks proxies are supported
proxies = {"https": "http://localhost:3128"}
r = curl_cffi.get("https://tls.browserleaks.com/json", impersonate="chrome", proxies=proxies)

proxies = {"https": "socks://localhost:3128"}
r = curl_cffi.get("https://tls.browserleaks.com/json", impersonate="chrome", proxies=proxies)

Sessions

v0.9:

from curl_cffi import requests

s = requests.Session()

v0.10:

s = curl_cffi.Session()

# httpbin is a http test website, this endpoint makes the server set cookies
s.get("https://httpbin.org/cookies/set/foo/bar")
print(s.cookies)
# <Cookies[<Cookie foo=bar for httpbin.org />]>

# retrieve cookies again to verify
r = s.get("https://httpbin.org/cookies")
print(r.json())
# {'cookies': {'foo': 'bar'}}

Supported impersonate browsers

curl_cffi supports the same browser versions as supported by my fork of curl-impersonate:

Open source version of curl_cffi includes versions whose fingerprints differ from previous versions.
If you see a version, e.g. chrome135, were skipped, you can simply impersonate it with your own headers and the previous version.

If you don’t want to look up the headers etc, by yourself, consider buying commercial support from impersonate.pro,
we have comprehensive browser fingerprints database for almost all the browser versions on various platforms.

If you are trying to impersonate a target other than a browser, use ja3=... and akamai=...
to specify your own customized fingerprints. See the docs on impersonation for details.

Browser	Open Source	Pro version
Chrome	chrome99, chrome100, chrome101, chrome104, chrome107, chrome110, chrome116[1], chrome119[1], chrome120[1], chrome123[3], chrome124[3], chrome131[4], chrome133a[5][6]	chrome132, chrome134, chrome135
Chrome Android	chrome99_android, chrome131_android [4]	chrome132_android, chrome133_android, chrome134_android, chrome135_android
Chrome iOS	N/A	coming soon
Safari	safari15_3 [2], safari15_5 [2], safari17_0 [1], safari18_0 [4],	coming soon
Safari iOS	safari17_2_ios[1], safari18_0_ios[4]	coming soon
Firefox	firefox133[5], firefox135[7]	coming soon
Firefox Android	N/A	firefox135_android
Edge	edge99, edge101	edge133, edge135
Opera	N/A	coming soon
Brave	N/A	coming soon

Notes:

1. Added in version 0.6.0.
2. Fixed in version 0.6.0, previous http2 fingerprints were not correct.
3. Added in version 0.7.0.
4. Added in version 0.8.0.
5. Added in version 0.9.0.
6. The version postfix -a(e.g. chrome133a) means that this is an alternative version, i.e. the fingerprint has not been officially updated by browser, but has been observed because of A/B testing.
7. Added in version 0.10.0.

Asyncio

from curl_cffi import AsyncSession

async with AsyncSession() as s:
    r = await s.get("https://example.com")

More concurrency:

import asyncio
from curl_cffi import AsyncSession

urls = [
    "https://google.com/",
    "https://facebook.com/",
    "https://twitter.com/",
]

async with AsyncSession() as s:
    tasks = []
    for url in urls:
        task = s.get(url)
        tasks.append(task)
    results = await asyncio.gather(*tasks)

WebSockets

from curl_cffi import WebSocket

def on_message(ws: WebSocket, message: str | bytes):
    print(message)

ws = WebSocket(on_message=on_message)
ws.run_forever("wss://api.gemini.com/v1/marketdata/BTCUSD")

For low-level APIs, Scrapy integration and other advanced topics, see the
docs for more details.

Asyncio WebSockets

import asyncio
from curl_cffi import AsyncSession

async with AsyncSession() as s:
    ws = await s.ws_connect("wss://echo.websocket.org")
    await asyncio.gather(*[ws.send_str("Hello, World!") for _ in range(10)])
    async for message in ws:
        print(message)

Acknowledgement

• Originally forked from multippt/python_curl_cffi, which is under the MIT license.
• Headers/Cookies files are copied from httpx, which is under the BSD license.
• Asyncio support is inspired by Tornado’s curl http client.
• The synchronous WebSocket API is inspired by websocket_client.
• The asynchronous WebSocket API is inspired by aiohttp.