FunBrowser

Undetect / anti-detect browser SDK for Python. Drives real Chrome through the DevTools Protocol with built-in stealth patches, customisable browser fingerprints (UA, GPU, screen, timezone, CPU cores, …), full proxy support, human-like input timing, browser-pool / context-pool farming, an optional local web panel, and automatic captcha solving for Cloudflare Turnstile, reCAPTCHA v2 / v3, hCaptcha, FunCaptcha, and GeeTest through funsolver.com.

Built for web scraping, browser automation, and bypassing antibot services (Cloudflare, DataDome, PerimeterX, Akamai) without the Selenium / Playwright leaks that get scripts flagged.

pip install funbrowser              # core: stealth + automation + solver
pip install funbrowser[panel]       # + local web panel for the pool
pip install funbrowser[tls]         # + browser-grade TLS impersonation

Quick start

import asyncio
import funbrowser

async def main():
    async with await funbrowser.start(headless=True) as browser:
        tab = await browser.get("https://example.com")
        print(await tab.evaluate("document.title"))
        # → Example Domain
        print(await tab.evaluate("navigator.userAgent"))
        # → Mozilla/5.0 ... Chrome/... — no "HeadlessChrome"

asyncio.run(main())

# Full automation: stealth + proxy + auto-solve captchas + humanly input
async with await funbrowser.start(
    headless=True,
    proxy="user:pass@us-1.proxy.io:8080",     # any common format works
    api_key="fs_xxx",                         # funsolver.com key
    humanly=True,                             # Bezier mouse + typing rhythm
    fingerprint=funbrowser.presets.windows_11_nvidia_rtx_4070(),
) as browser:
    tab = await browser.get("https://target-with-captcha.com")
    # captchas auto-solve in the background
    await tab.fill("#email", "alice@example.com")
    await tab.click("button[type=submit]")

Features

Stealth (passes 25/25 standard antidetect probes)

• navigator.webdriver → undefined, with native toString camouflage
• UA + Client Hints with HeadlessChrome stripped
• chrome.runtime, plugins, languages, permissions consistency
• Real GPU for WebGL (--use-gl=angle, not SwiftShader)
• Canvas + audio readout noise to break fingerprint tracking
• WebRTC IP leak blocked (flag-level + SDP filter)
• iframe stealth propagation
• Geo auto-couples timezone + locale to proxy exit IP

uv run python examples/detect_check.py      # self-audit

Fingerprint customisation

17 ready presets (Windows × NVIDIA / Intel / AMD, macOS Apple Silicon / Intel, Linux, plus 4 Android mobile) + arbitrary custom Fingerprint(...).

from funbrowser import Fingerprint, presets

fp = presets.macos_apple_silicon_m3_pro().merge(
    Fingerprint(timezone="Asia/Tokyo", languages=("ja-JP", "ja", "en"))
)
async with await funbrowser.start(fingerprint=fp) as browser:
    ...

Humanly mode (Bezier-curve mouse + typing rhythm)

async with await funbrowser.start(humanly=True) as browser:
    await tab.click("button")        # cursor curves toward target
    await tab.type("#email", "ada")  # per-keystroke random delay

Presets: humanly.FAST, humanly.DEFAULT, humanly.CAREFUL, plus arbitrary custom HumanBehavior(...).

Captcha auto-solve

Paste a funsolver.com API key. Five captcha families detected on-page and solved automatically:

Proxies (every format)

host:port, host:port:user:pass, user:pass@host:port, host:port@user:pass, socks5://..., chrome URL form — all auto-parsed. HTTP/HTTPS auth flows through CDP automatically.

Persistent profiles

from funbrowser import Profile

alice = Profile.ensure("alice")   # ./funbrowser_profiles/alice
async with await funbrowser.start(user_data_dir=alice) as browser:
    # cookies + localStorage + login state persist between runs
    ...

Browser farming — BrowserPool and ContextPool

from funbrowser import BrowserPool, ContextPool

# Process pool — full Chrome per slot (max isolation)
async with BrowserPool(
    size=5,
    proxies=["proxy1:8080", "proxy2:8080", "proxy3:8080"],
    headless=True,
    mini=True,
) as pool:
    async def scrape(browser):
        tab = await browser.get("https://example.com")
        return await tab.evaluate("document.title")

    results = await pool.run_all([scrape] * 100)

# Context pool — 1 Chrome + N isolated contexts (~7-10x less RAM)
async with ContextPool(size=10, headless=True, mini=True) as pool:
    async def scrape(ctx):
        tab = await ctx.get("https://example.com")
        return await tab.evaluate("document.title")

    results = await pool.run_all([scrape] * 100)

Memory comparison on the same 10-slot workload:

• BrowserPool(size=10) → ~1.0 GB
• ContextPool(size=10) → ~260 MB (one Chrome + 10 contexts)

mini=True mode

Curated set of Chrome flags that cut RAM / CPU / disk per browser (~50% lower RSS): site isolation off, background throttling, audio muted, extensions / sync / translate disabled, small disk caches, V8 heap cap. Combines with stealth — does not turn off the real GPU. Works on Browser, BrowserPool, and ContextPool alike.

TLS fingerprint impersonation (pip install funbrowser[tls])

Script-level HTTP that picks JA3/JA4 from real-browser profiles:

from funbrowser.tls import ImpersonatedHTTPClient

async with ImpersonatedHTTPClient(profile="chrome131") as http:
    r = await http.get("https://protected-api.com/endpoint")

23 supported profiles: chrome99..chrome133a, safari15..safari18, firefox133/135, Android variants. See docs/M10_M11_DESIGN.md for the deeper browser-traffic mitm proxy roadmap.

Local web panel (pip install funbrowser[panel])

from funbrowser import BrowserPool, Panel

async with BrowserPool(size=5) as pool:
    async with Panel(pool) as panel:
        print(panel.url)   # http://127.0.0.1:8765
        await long_running_task()

Black-and-white dashboard with: pool stats, FunSolver balance, browser fleet table (proxy / geo / fingerprint / open tabs / per-row goto + screenshot), activity log (panel actions + per-browser captcha solves), quick actions, and a script runner — upload an async def main(browser) script and run it on one browser or fan it out across the whole pool, with per-run stdout / return / traceback captured.

Documentation

• docs/stealth.md — anti-detect coverage in depth
• docs/captchas.md — solver integration guide
• docs/farming.md — BrowserPool vs ContextPool
• docs/panel.md — the local web dashboard
• docs/M10_M11_DESIGN.md — TLS + engine-layer roadmap
• examples/ — runnable demos for every feature

Self-audit

uv run python examples/detect_check.py

[navigator.* basics]              9/9   PASS
[chrome runtime + iframe]         6/6   PASS
[stealth-detection probes]        5/5   PASS
[WebGL / canvas / audio]          4/4   PASS
[WebRTC IP leak]                  1/1   PASS

score:     25/25  (100%)

Roadmap

Development

Uses uv for env + deps.

uv sync                              # install
uv run pytest -q                     # full test suite (173 tests)
uv run ruff check . && uv run ruff format --check .
uv run mypy funbrowser
uv run python examples/detect_check.py

Contributing

See CONTRIBUTING.md. Issues + PRs welcome.

License

MIT. See LICENSE.