<h3 align="center">Stealth Chromium that passes every bot detection test.</h3>
<table><tr><td>
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 <em>is</em> a normal browser.
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.
```bash
docker run -p 8080:8080 -v cloakprofiles:/data cloakhq/cloakbrowser-manager
```
Open [http://localhost:8080](http://localhost:8080). Create a profile. Click **Launch**. Done.
→ **[CloakBrowser Manager](https://github.com/CloakHQ/CloakBrowser-Manager)** — free, open source (MIT)
- **`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.
- **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)
- **`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
- **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.
- **Works with AI agents and automation frameworks** — drop-in stealth for browser-use, Crawl4AI, Scrapling, Stagehand, LangChain, Selenium, and more. See [integrations](#framework-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.
Extra kwargs are forwarded to Playwright's `browser.new_context()` — use this for `storage_state`, `permissions`, `extra_http_headers`, etc. without needing a persistent profile folder:
```python
fromcloakbrowserimportlaunch_context
# Restore a saved session (cookies, localStorage) from a JSON file
**Storage quota and detection tradeoff:** By default, the binary normalizes storage quota to pass FingerprintJS, which blocks persistent contexts that report non-incognito quota values. This means detection services that penalize incognito mode (like BrowserScan's `notPrivate` check, -10 points) will still flag it. If your target site penalizes incognito but doesn't use FingerprintJS, set a higher quota to appear as a regular profile:
> **Note:** The Playwright wrapper is recommended for sites with reCAPTCHA Enterprise. Puppeteer's CDP protocol leaks automation signals that reCAPTCHA Enterprise can detect, causing intermittent 403 errors. This is a known Puppeteer limitation, not specific to CloakBrowser. Use Playwright for best results.
Pass `humanize=True` to make all mouse, keyboard, and scroll interactions indistinguishable from real users. All Playwright calls (`page.click()`, `page.fill()`, `page.type()`, `page.mouse.*`, `page.keyboard.*`, Locator API) and Puppeteer calls (`page.click()`, `page.type()`, `page.mouse.*`, `page.keyboard.*`, ElementHandle API) are automatically replaced with human-like equivalents. No code changes needed.
> **Note (Playwright):** Always use `page.click(selector)`, `page.type(selector, text)`, `page.hover(selector)`, or `page.locator(selector).*` — these go through the full humanize pipeline. Avoid `page.query_selector()` — `ElementHandle` objects bypass all patches, so mouse movement teleports, keyboard events fire without timing, and scroll has no human curve.
>
> **Note (Puppeteer):** Both selector-based methods (`page.click()`, `page.type()`) and ElementHandle methods (`el.click()`, `el.type()`) are fully humanized. `page.$()`, `page.$$()`, and `page.waitForSelector()` return patched handles automatically.
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:
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:
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.
| `--fingerprint-storage-quota` | Override storage quota in MB — affects `storage.estimate()`, `storageBuckets`, and legacy webkit APIs. Auto-normalized when `--fingerprint` is set |
| `--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` |
> **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.
**Required for aggressive anti-bot sites (Kasada, Akamai).** When running on Linux, installing Windows fonts changes how the browser renders text on canvas, which directly affects canvas fingerprint hashes. Without Windows fonts, anti-bot systems detect the Linux font rendering as inconsistent with a Windows profile and block the request. This applies even without the `--fingerprint-fonts-dir` flag — the fonts just need to be installed on the system.
```bash
# 1. Copy fonts from a Windows machine's C:\Windows\Fonts\ directory
# (ttf-mscorefonts-installer only has old XP-era fonts — not enough)
> **Humanize over CDP**: Stealth fingerprint patches work automatically over CDP, but `humanize=True` is a wrapper-level feature. If you connect to CloakBrowser via CDP from a separate script, import the patching functions to add humanization:
>
> ```js
> import { patchBrowser, resolveConfig } from 'cloakbrowser/human';
**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.
**Per-connection fingerprint seeds** — run multiple browser identities from a single container. Each unique seed spawns a separate Chrome process with its own fingerprint:
```python
# Each seed gets unique canvas noise, client rects, and other browser signals
Supported query params: `fingerprint`, `timezone`, `locale`, `platform`, `platform-version`, `brand`, `brand-version`, `gpu-vendor`, `gpu-renderer`, `hardware-concurrency`, `device-memory`, `screen-width`, `screen-height`, `proxy`, `geoip`. Same seed reuses the same process (first connection's params win). No seed = shared default process (backward compatible). Check active processes at `GET /` (returns JSON with PIDs, ports, and connection counts).
This runs a real headed browser rendered on a virtual display — no physical monitor needed. Combine with the recommended config below for maximum stealth.
---
### Recommended config for anti-bot sites
Most blocks come from missing one of these three things, not from browser fingerprint detection:
```python
browser=launch(
proxy="http://your-residential-proxy:port",# residential IP — datacenter IPs get blocked by reputation alone
geoip=True,# matches timezone + locale to proxy exit IP (without this: UTC + en-US = bot signal)
headless=False,# headed mode — some sites detect headless even with C++ patches
If your proxy supports SOCKS5, use it for better compatibility — SOCKS5 tunnels raw TCP, avoiding HTTP CONNECT issues that some proxies have with HTTP/2:
If you're still blocked after this, check the font setup below.
---
### Blocked on Kasada / Akamai sites despite correct config?
On Linux, missing Windows fonts changes how the browser renders canvas text, producing fingerprint hashes that anti-bot systems flag as inconsistent with a Windows profile. This is the most common cause of blocks on aggressive sites after proxy, geoip, and headed mode are already set up correctly.
Install Windows fonts on your system — see [Font Setup on Linux](#font-setup-on-linux) above.
Some sites challenge first-time visitors with no cookies over HTTP/2. This affects all Chromium browsers, not just CloakBrowser. Use a persistent profile to warm up cookies once, then reuse across sessions:
For stateless/ephemeral use cases, `launch(args=["--disable-http2"])` forces HTTP/1.1 which bypasses the check. Only use this flag for sites that require it — most work fine with HTTP/2. If your proxy supports SOCKS5, use `proxy="socks5://user:pass@host:port"` instead — SOCKS5 bypasses HTTP CONNECT entirely.
The macOS fingerprint profile has known inconsistencies that aggressive bot detection catches. If a site blocks you on macOS but works on Linux, switch to a Windows fingerprint profile by passing `stealth_args=False` and manually setting `--fingerprint-platform=windows` with matching GPU flags (see [Fingerprint Management](#fingerprint-management) for the full flag list).
By default, `launch()` opens an incognito context. Some sites penalize this. Use `launch_persistent_context()` to get a real profile with cookie persistence:
If the site still flags incognito, raise the storage quota to appear as a regular browsing session. See the [storage quota tradeoff](#launch_persistent_context) for details on how this affects different detection services.
- **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 ([details](#puppeteer))
- **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 `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:
```python
page.type("#email", "user@example.com", delay=50)
```
- **Minimize `page.evaluate()` calls** before the reCAPTCHA check fires — each one sends CDP traffic
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. See [BINARY-LICENSE.md](https://github.com/CloakHQ/CloakBrowser/blob/main/BINARY-LICENSE.md) for full terms.
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.
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.
- **Wrapper code** (this repository) — MIT. See [LICENSE](https://github.com/CloakHQ/CloakBrowser/blob/main/LICENSE).
- **CloakBrowser binary** (compiled Chromium) — free to use, no redistribution. See [BINARY-LICENSE.md](https://github.com/CloakHQ/CloakBrowser/blob/main/BINARY-LICENSE.md).
