Stealth Chromium that passes every bot detection test.

Not a patched config. Not a JS injection. A real Chromium binary with fingerprints modified at the C++ source level. Antibot systems score it as a normal browser — because it is a normal browser.

Cloudflare Turnstile — 3 live tests passing (headed mode, macOS)

Drop-in Playwright/Puppeteer replacement for Python and JavaScript.
Same API, same code — just swap the import. 3 lines of code, 30 seconds to unblock.

• 49 source-level C++ patches — canvas, WebGL, audio, fonts, GPU, screen, WebRTC, network timing, automation signals, CDP input behavior
• humanize=True — human-like mouse curves, keyboard timing, and scroll patterns. One flag, behavioral detection passes
• 0.9 reCAPTCHA v3 score — human-level, server-verified
• Passes Cloudflare Turnstile, FingerprintJS, BrowserScan — tested against 30+ detection sites
• Auto-updating binary — background update checks, always on the latest stealth build
• pip install cloakbrowser or npm install cloakbrowser — binary auto-downloads, zero config
• Free and open source — no subscriptions, no usage limits

Install

Download the latest build from the Releases page.

Platform	File
macOS	.dmg
Linux (any)	.AppImage
Windows	.exe

Browser Profile Manager

Self-hosted alternative to Multilogin, GoLogin, and AdsPower. Create browser profiles with unique fingerprints, proxies, and persistent sessions. Launch and interact with them in your browser via noVNC.

Open http://localhost:8080. Create a profile. Click Launch. Done.

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Latest: v0.3.26 (Chromium 146.0.7680.177.4)

• launch_context_async() — async counterpart to launch_context(). Forwards kwargs to browser.new_context() for storage_state, permissions, extra_http_headers without a persistent profile folder.
• JS contextOptions escape hatch — forward arbitrary options (including storageState) to Playwright's newContext() from launchContext() / launchPersistentContext().
• Native SOCKS5 proxy — proxy="socks5://user:pass@host:port" works directly in all launch functions, Python + JS. QUIC/HTTP3 tunnels through SOCKS5 via UDP ASSOCIATE.
• Chromium 146 upgrade — rebased all patches from 145.0.7632.x to 146.0.7680.177
• 57 fingerprint patches — additional detection-vector coverage (WebAuthn, AAC audio, window position) and WebGL/canvas consistency fixes
• WebRTC IP spoofing — --fingerprint-webrtc-ip=auto resolves your proxy's exit IP and spoofs WebRTC ICE candidates. Auto-injected when using geoip=True (no extra network call)
• Proxy signal removal — DNS/connect/SSL timing zeroed, proxy cache headers stripped, Proxy-Connection header leak removed
• cloakserve CDP multiplexer — rewritten as a multi-connection CDP proxy with per-connection fingerprint seeds
• Humanize CDP isolation — keyboard events now use isolated worlds and trusted dispatch for better behavioral stealth
• humanize=True — one flag makes all mouse, keyboard, and scroll interactions behave like a real user. Bézier curves, per-character typing, realistic scroll patterns
• Stealthy with zero flags — binary auto-generates a random fingerprint seed at startup. No configuration required
• Timezone & locale from proxy IP — launch(proxy="...", geoip=True) auto-detects timezone and locale
• Persistent profiles — launch_persistent_context() keeps cookies and localStorage across sessions, bypasses incognito detection

Why CloakBrowser?

• Config-level patches break — playwright-stealth, undetected-chromedriver, and puppeteer-extra inject JavaScript or tweak flags. Every Chrome update breaks them. Antibot systems detect the patches themselves.
• CloakBrowser patches Chromium source code — fingerprints are modified at the C++ level, compiled into the binary. Detection sites see a real browser because it is a real browser.
• Source-level stealth — C++ patches handle fingerprints (GPU, screen, UA, hardware reporting) at the binary level. No JavaScript injection, no config-level hacks. Most stealth tools only patch at the surface.
• Same behavior everywhere — works identically local, in Docker, and on VPS. No environment-specific patches or config needed.
• Works with AI agents and automation frameworks — drop-in stealth for browser-use, Crawl4AI, Scrapling, Stagehand, LangChain, Selenium, and more. See integrations.

CloakBrowser doesn't solve CAPTCHAs — it prevents them from appearing. No CAPTCHA-solving services, no proxy rotation built in — bring your own proxies, use the Playwright API you already know.

Test Results

All tests verified against live detection services. Last tested: Apr 2026 (Chromium 146).

Detection Service	Stock Playwright	CloakBrowser	Notes
reCAPTCHA v3	0.1 (bot)	0.9 (human)	Server-side verified
Cloudflare Turnstile (non-interactive)	FAIL	PASS	Auto-resolve
Cloudflare Turnstile (managed)	FAIL	PASS	Single click
ShieldSquare	BLOCKED	PASS	Production site
FingerprintJS bot detection	DETECTED	PASS	demo.fingerprint.com
BrowserScan bot detection	DETECTED	NORMAL (4/4)	browserscan.net
bot.incolumitas.com	13 fails	1 fail	WEBDRIVER spec only
deviceandbrowserinfo.com	6 true flags	0 true flags	isBot: false
navigator.webdriver	true	false	Source-level patch
navigator.plugins.length	0	5	Real plugin list
window.chrome	undefined	object	Present like real Chrome
UA string	HeadlessChrome	Chrome/146.0.0.0	No headless leak
CDP detection	Detected	Not detected	isAutomatedWithCDP: false
TLS fingerprint	Mismatch	Identical to Chrome	ja3n/ja4/akamai match
		Tested against 30+ detection sites

Proof

reCAPTCHA v3 score 0.9 — server-side verified (human-level)

Cloudflare Turnstile non-interactive challenge — auto-resolved

BrowserScan bot detection — NORMAL (4/4 checks passed)

FingerprintJS web-scraping demo — data served, not blocked

deviceandbrowserinfo.com behavioral bot detection — "You are human!" with humanize=True (24/24 signals passed)

Comparison

Feature	Playwright	playwright-stealth	undetected-chromedriver	Camoufox	CloakBrowser
reCAPTCHA v3 score	0.1	0.3-0.5	0.3-0.7	0.7-0.9	0.9
Cloudflare Turnstile	Fail	Sometimes	Sometimes	Pass	Pass
Patch level	None	JS injection	Config patches	C++ (Firefox)	C++ (Chromium)
Survives Chrome updates	N/A	Breaks often	Breaks often	Yes	Yes
Maintained	Yes	Stale	Stale	Unstable	Active
Browser engine	Chromium	Chromium	Chrome	Firefox	Chromium
Playwright API	Native	Native	No (Selenium)	No	Native

How It Works

CloakBrowser is a thin wrapper (Python + JavaScript) around a custom-built Chromium binary:

1. You install → pip install cloakbrowser or npm install cloakbrowser
2. First launch → binary auto-downloads for your platform (Chromium 146)
3. Every launch → Playwright or Puppeteer starts with our binary + stealth args
4. You write code → standard Playwright/Puppeteer API, nothing new to learn

The binary includes 49 source-level patches covering canvas, WebGL, audio, fonts, GPU, screen properties, WebRTC, network timing, hardware reporting, automation signal removal, and CDP input behavior mimicking.

These are compiled into the Chromium binary — not injected via JavaScript, not set via flags.

Binary downloads are verified with SHA-256 checksums to ensure integrity.

Configuration

Env Variable	Default	Description
CLOAKBROWSER_BINARY_PATH	—	Skip download, use a local Chromium binary
CLOAKBROWSER_CACHE_DIR	~/.cloakbrowser	Binary cache directory
CLOAKBROWSER_DOWNLOAD_URL	cloakbrowser.dev	Custom download URL for binary
CLOAKBROWSER_AUTO_UPDATE	true	Set to false to disable background update checks
CLOAKBROWSER_SKIP_CHECKSUM	false	Set to true to skip SHA-256 verification after download
CLOAKBROWSER_GEOIP_TIMEOUT_SECONDS	5	Max seconds for GeoIP resolution before continuing without it

Fingerprint Management

The binary is stealthy by default — no flags needed. It auto-generates a random fingerprint seed at startup and spoofs all detectable values (GPU, hardware specs, screen dimensions, canvas, WebGL, audio, fonts). Every launch produces a fresh, coherent identity.

How fingerprinting works:

Scenario	What happens
No flags	Random seed auto-generated at startup. GPU, screen, hardware specs, and all noise patches are spoofed automatically. Fresh identity each launch.
--fingerprint=seed	Deterministic identity from the seed. Same seed = same fingerprint across launches. Use this for session persistence (returning visitor).
--fingerprint=seed + explicit flags	Explicit flags override individual auto-generated values. The seed fills in everything else.

The binary detects its platform at compile time — a macOS binary reports as macOS with Apple GPU, a Linux binary reports as Linux with NVIDIA GPU. The wrapper overrides this on Linux by passing --fingerprint-platform=windows, so sessions appear as Windows desktops (more common fingerprint, harder to cluster). Use --fingerprint-platform for cross-platform spoofing when running the binary directly.

Tip: Use a fixed seed when revisiting the same site. A random seed makes every session look like a different device — which can be suspicious when hitting the same site repeatedly from the same IP. For reCAPTCHA v3 Enterprise and similar scoring systems, a fixed seed produces a consistent fingerprint across sessions, making you look like a returning visitor:

browser = launch(args=["--fingerprint=12345"])

const browser = await launch({ args: ['--fingerprint=12345'] });

Default Fingerprint

Every launch() call sets these automatically. The wrapper applies platform-aware defaults — on Linux it spoofs as Windows for a more common fingerprint, on macOS it runs as a native Mac browser:

Flag	Linux/Windows Default	macOS Default	Controls
--fingerprint	Random (10000–99999)	Random (10000–99999)	Master seed for canvas, WebGL, audio, fonts, client rects
--fingerprint-platform	windows	macos	navigator.platform, User-Agent OS, GPU pool selection

The binary auto-generates everything else from the seed: GPU, hardware concurrency, device memory, and screen dimensions. Each seed produces a unique, consistent fingerprint. Override with explicit flags if needed.

Using the binary directly? It works out of the box with zero flags -- the binary auto-spoofs everything. Pass --fingerprint=seed for a persistent identity, or use explicit flags like --fingerprint-gpu-renderer to override any auto-generated value.

Additional Flags

Supported by the binary but not set by default — pass via args to customize:

Flag	Controls
--fingerprint-gpu-vendor	WebGL UNMASKED_VENDOR_WEBGL (auto-generated from seed + platform)
--fingerprint-gpu-renderer	WebGL UNMASKED_RENDERER_WEBGL (auto-generated from seed + platform)
--fingerprint-hardware-concurrency	navigator.hardwareConcurrency (auto-generated: 8)
--fingerprint-device-memory	navigator.deviceMemory in GB (auto-generated: 8)
--fingerprint-screen-width	Screen width (auto-generated: 1920 Win/Linux, 1440 macOS)
--fingerprint-screen-height	Screen height (auto-generated: 1080 Win/Linux, 900 macOS)
--fingerprint-brand	Browser brand: Chrome, Edge, Opera, Vivaldi
--fingerprint-brand-version	Brand version (UA + Client Hints)
--fingerprint-platform-version	Client Hints platform version
--fingerprint-location	Geolocation coordinates
--fingerprint-timezone	Timezone (e.g. America/New_York)
--fingerprint-locale	Locale (e.g. en-US)
--fingerprint-storage-quota	Override storage quota in MB — affects storage.estimate(), storageBuckets, and legacy webkit APIs. Auto-normalized when --fingerprint is set
--fingerprint-taskbar-height	Override taskbar height (binary defaults: Win=48, Mac=95, Linux=0)
--fingerprint-fonts-dir	Path to directory containing target-platform fonts
--fingerprint-webrtc-ip	WebRTC ICE candidate IP replacement. Use auto to resolve from proxy exit IP (makes an HTTP call through the proxy), or pass an explicit IP. Auto-injected when geoip=True
--fingerprint-noise=false	Disable noise injection (canvas, WebGL, audio, client rects) while keeping the deterministic fingerprint seed active
--enable-blink-features=FakeShadowRoot	Access closed shadow DOM elements

Note: All stealth tests were verified with the default fingerprint config above. Changing these flags may affect detection results — test your configuration before using in production.

Platforms

Platform	Chromium	Patches	Status
Linux x86_64	146	57	✅ Latest
Linux arm64 (RPi, Graviton)	146	57	✅ Latest
macOS arm64 (Apple Silicon)	145	26	✅
macOS x86_64 (Intel)	145	26	✅
Windows x86_64	146	57	✅ Latest

The wrapper auto-downloads the correct binary for your platform.

macOS first launch: The binary is ad-hoc signed. On first run, macOS Gatekeeper will block it. Right-click the app → Open → click Open in the dialog. This is only needed once.

Troubleshooting

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reCAPTCHA v3 scores are low (0.1–0.3)

Avoid page.wait_for_timeout() — it sends CDP protocol commands that reCAPTCHA detects. Use native sleep instead:

# Bad — sends CDP commands, reCAPTCHA detects this
page.wait_for_timeout(3000)

# Good — invisible to the browser
import time
time.sleep(3)

// Bad — sends CDP commands
await page.waitForTimeout(3000);

// Good — invisible to the browser
await new Promise(r => setTimeout(r, 3000));

Other tips for maximizing reCAPTCHA scores:

• Try the Patchright backend — suppresses additional CDP automation signals at the Playwright protocol layer. Install with pip install cloakbrowser[patchright], then use launch(backend="patchright") or set CLOAKBROWSER_BACKEND=patchright globally. Note: Patchright breaks proxy auth and add_init_script — only use it if you're still seeing low scores after trying the steps above
• Use Playwright, not Puppeteer — Puppeteer sends more CDP protocol traffic that reCAPTCHA detects
• Use residential proxies — datacenter IPs are flagged by IP reputation, not browser fingerprint
• Spend 15+ seconds on the page before triggering reCAPTCHA — short visits score lower
• Space out requests — back-to-back grecaptcha.execute() calls from the same session get penalized. Wait 30+ seconds between pages with reCAPTCHA
• Use a fixed fingerprint seed for consistent device identity across sessions
• Use page.type() instead of page.fill() for form filling — fill() sets values directly without keyboard events, which reCAPTCHA's behavioral analysis flags. type() with a delay simulates real keystrokes:

  page.type("#email", "user@example.com", delay=50)

• Minimize page.evaluate() calls before the reCAPTCHA check fires — each one sends CDP traffic

FAQ

Q: Is this legal? A: CloakBrowser is a browser built on open-source Chromium. We do not condone illegal use. Automating systems without authorization, credential stuffing, and account creation abuse are expressly prohibited.

Q: How is this different from Camoufox? A: Camoufox patches Firefox. We patch Chromium. Chromium means native Playwright support, larger ecosystem, and TLS fingerprints that match real Chrome. Camoufox returned in early 2026 but is in unstable beta — CloakBrowser is production-ready.

Q: Will detection sites eventually catch this? A: Possibly. Bot detection is an arms race. Source-level patches are harder to detect than config-level patches, but not impossible. We actively monitor and update when detection evolves.

Q: Can I use my own proxy? A: Yes. Pass proxy="http://user:pass@host:port" or proxy="socks5://user:pass@host:port" to launch(). Both HTTP and SOCKS5 proxies are supported natively.

Roadmap

Feature	Status
Linux x64 — Chromium 146 (57 patches)	✅ Released
macOS arm64/x64 — Chromium 145 (26 patches)	✅ Released
Windows x64 — Chromium 146 (57 patches)	✅ Released
JavaScript/Puppeteer + Playwright support	✅ Released
Fingerprint rotation per session	✅ Released
Built-in proxy rotation	📋 Planned

License

• CloakBrowser binary (compiled Chromium) — free to use, no redistribution. See LICENSE.md.