# CloakBrowser
[](https://www.npmjs.com/package/cloakbrowser)
[](https://github.com/CloakHQ/CloakBrowser/blob/main/LICENSE)
**Stealth Chromium that passes every bot detection test.**
Drop-in Playwright/Puppeteer replacement. Same API, same code — just swap the import. **3 lines of code, 30 seconds to unblock.**
- **58 source-level C++ patches** — canvas, WebGL, audio, fonts, GPU, screen, WebRTC, network timing, automation signals
- **0.9 reCAPTCHA v3 score** — human-level, server-verified
- **Passes Cloudflare Turnstile**, FingerprintJS, BrowserScan — tested against 30+ detection sites
- **`npm install cloakbrowser`** — binary auto-downloads, auto-updates, zero config
- **Free and open source** — no subscriptions, no usage limits
- **Works with any framework** — tested with browser-use, Crawl4AI, Scrapling, Stagehand ([example](examples/stagehand.ts)), LangChain, Selenium, and more
## Install
```bash
# With Playwright
npm install cloakbrowser playwright-core
# With Puppeteer
npm install cloakbrowser puppeteer-core
```
On first launch, the stealth Chromium binary auto-downloads (~200MB, cached at `~/.cloakbrowser/`).
## Usage
### Playwright (default)
```javascript
import { launch } from 'cloakbrowser';
const browser = await launch();
const page = await browser.newPage();
await page.goto('https://example.com');
console.log(await page.title());
await browser.close();
```
**For sites with anti-bot protection**, add a residential proxy and these flags:
```javascript
const browser = await launch({
proxy: 'http://user:pass@residential-proxy:port',
geoip: true, // match timezone + locale to proxy IP
headless: false, // some sites detect headless even with C++ patches
humanize: true, // human-like mouse, keyboard, scroll
});
```
See the [main README](https://github.com/CloakHQ/CloakBrowser#troubleshooting) for site-specific troubleshooting (FingerprintJS, Kasada, reCAPTCHA).
### Puppeteer
> **Note:** Playwright is recommended for sites with reCAPTCHA Enterprise. Puppeteer's CDP protocol leaks automation signals that reCAPTCHA Enterprise can detect. This is a known Puppeteer limitation, not specific to CloakBrowser.
```javascript
import { launch } from 'cloakbrowser/puppeteer';
const browser = await launch();
const page = await browser.newPage();
await page.goto('https://example.com');
console.log(await page.title());
await browser.close();
```
### Options
```javascript
import { launch, launchContext, launchPersistentContext } from 'cloakbrowser';
// With proxy (HTTP or SOCKS5)
const browser = await launch({
proxy: 'http://user:pass@proxy:8080',
});
const browser = await launch({
proxy: 'socks5://user:pass@proxy:1080',
});
// With proxy object (bypass, separate auth fields)
const browser = await launch({
proxy: { server: 'http://proxy:8080', bypass: '.google.com', username: 'user', password: 'pass' },
});
// Headed mode (visible browser window)
const browser = await launch({ headless: false });
// Extra Chrome args
const browser = await launch({
args: ['--fingerprint=12345'],
});
// With timezone and locale
const browser = await launch({
timezone: 'America/New_York',
locale: 'en-US',
});
// Auto-detect timezone/locale from proxy IP (requires: npm install mmdb-lib)
const browser = await launch({
proxy: 'http://proxy:8080',
geoip: true,
});
// Browser + context in one call (timezone/locale set via binary flags)
const context = await launchContext({
userAgent: 'Custom UA',
viewport: { width: 1920, height: 1080 },
locale: 'en-US',
timezone: 'America/New_York',
});
// Persistent profile — stay logged in, bypass incognito detection, load extensions
const ctx = await launchPersistentContext({
userDataDir: './chrome-profile',
headless: false,
proxy: 'http://user:pass@proxy:8080',
});
const page = ctx.pages()[0] || await ctx.newPage();
await page.goto('https://example.com');
await ctx.close(); // profile saved — reuse same path to restore state
```
### Auto Timezone/Locale from Proxy IP
When using a proxy, antibot systems check that your browser's timezone and locale match the proxy's location. Install `mmdb-lib` to enable auto-detection from an offline GeoIP database (~70 MB, downloaded on first use):
```bash
npm install mmdb-lib
```
```javascript
// Auto-detect — timezone and locale set from proxy's IP geolocation
const browser = await launch({ proxy: 'http://proxy:8080', geoip: true });
// Works with launchContext too
const context = await launchContext({ proxy: 'http://proxy:8080', geoip: true });
// Explicit values always win over auto-detection
const browser = await launch({ proxy: 'http://proxy:8080', geoip: true, timezone: 'Europe/London' });
```
> **Note:** For rotating residential proxies, the DNS-resolved IP may differ from the exit IP. Pass explicit `timezone`/`locale` in those cases.
### CLI
Pre-download the binary or check installation status from the command line:
```bash
npx cloakbrowser install # Download binary with progress output
npx cloakbrowser info # Show version, path, platform
npx cloakbrowser update # Check for and download newer binary
npx cloakbrowser clear-cache # Remove cached binaries
```
### Utilities
```javascript
import { ensureBinary, clearCache, binaryInfo, checkForUpdate } from 'cloakbrowser';
// Pre-download binary (e.g., during Docker build)
await ensureBinary();
// Check installation
console.log(binaryInfo());
// Force re-download
clearCache();
// Manually check for newer Chromium version
const newVersion = await checkForUpdate();
if (newVersion) console.log(`Updated to ${newVersion}`);
```
## Test Results
| Detection Service | Stock Browser | CloakBrowser |
|---|---|---|
| **reCAPTCHA v3** | 0.1 (bot) | **0.9** (human) |
| **Cloudflare Turnstile** | FAIL | **PASS** |
| **FingerprintJS** | DETECTED | **PASS** |
| **BrowserScan** | DETECTED | **NORMAL** (4/4) |
| **bot.incolumitas.com** | 13 fails | **1 fail** |
| `navigator.webdriver` | `true` | **`false`** |
| CDP detection | Detected | **Not detected** |
| TLS fingerprint | Mismatch | **Identical to Chrome** |
| | | **Tested against 30+ detection sites** |
## 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 |
| `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_WIDEVINE_CDM` | — | Path to a sideloaded `WidevineCdm` directory (overrides auto-detection next to the binary) |
| `CLOAKBROWSER_WIDEVINE` | `1` | Set to `0` to disable automatic Widevine hint-file seeding for persistent contexts |
### Widevine / DRM
The binary supports Widevine, but the CDM is proprietary and can't be redistributed. Sideload it once by copying a `WidevineCdm/` directory from a real Chrome install next to the binary (full steps in [#96](https://github.com/CloakHQ/CloakBrowser/issues/96)):
```bash
cp -r /opt/google/chrome/WidevineCdm ~/.cloakbrowser/chromium-/WidevineCdm
```
With the CDM in place, `launchPersistentContext()` enables Widevine on the **first** launch — the wrapper auto-seeds the CDM hint file into the profile. This plays DRM-protected video (Netflix, Spotify Web) and makes a persistent profile present as a regular Chrome install to detection services that probe for DRM/EME support. **Linux only.** A sideloaded CDM is the opt-in (no flag); set `CLOAKBROWSER_WIDEVINE_CDM` for a custom path or `CLOAKBROWSER_WIDEVINE=0` to disable. See the [main README](https://github.com/CloakHQ/CloakBrowser#widevine--drm) for details.
## Migrate From Playwright
```diff
- import { chromium } from 'playwright';
- const browser = await chromium.launch();
+ import { launch } from 'cloakbrowser';
+ const browser = await launch();
const page = await browser.newPage();
// ... rest of your code works unchanged
```
## Platforms
| Platform | Chromium | Patches | Status |
|---|---|---|---|
| Linux x86_64 | 146 | 58 | ✅ Latest |
| Linux arm64 (RPi, Graviton) | 146 | 58 | ✅ |
| macOS arm64 (Apple Silicon) | 145 | 26 | ✅ |
| macOS x86_64 (Intel) | 145 | 26 | ✅ |
| Windows x86_64 | 146 | 58 | ✅ Latest |
## CloakBrowser Pro
The wrapper (Python + JS) is MIT, free forever. The binary uses a delayed
free-release model:
- **Free (v146)** — free forever on [GitHub Releases](https://github.com/CloakHQ/cloakbrowser/releases). Unlimited sessions. Works today, goes stale as detection evolves.
- **Pro (latest, v148)** — the newest patches and Chromium upgrades first, so the [test results](#test-results) stay green as anti-bot systems change. Linux + Windows (macOS coming).
Anti-bot detection updates constantly — an older binary degrades within weeks.
Pro keeps you on the build that's actively maintained against it.
Activate with your license key (env var, `licenseKey` option, or `~/.cloakbrowser/license.key`):
```bash
export CLOAKBROWSER_LICENSE_KEY=cb_xxxxxxxx
```
Pro plans → **[cloakbrowser.dev](https://cloakbrowser.dev)**
## Requirements
- Node.js >= 20
- One of: `playwright-core` >= 1.53 or `puppeteer-core` >= 21
## Troubleshooting
**Site detects incognito / private browsing mode**
By default, `launch()` opens an incognito context. Some sites (like BrowserScan) detect this. Use `launchPersistentContext()` instead — it runs with a real user profile:
```javascript
import { launchPersistentContext } from 'cloakbrowser';
const ctx = await launchPersistentContext({
userDataDir: './my-profile',
headless: false,
});
// Load Chrome extensions
const ctx = await launchPersistentContext({
userDataDir: './my-profile',
headless: false,
extensionPaths: ['./my-extension'],
});
```
This also gives you cookie and localStorage persistence across sessions.
**reCAPTCHA v3 scores are low (0.1–0.3)**
Avoid `page.waitForTimeout()` — it sends CDP protocol commands that reCAPTCHA detects. Use native sleep instead:
```javascript
// Bad — sends CDP commands, reCAPTCHA detects this
await page.waitForTimeout(3000);
// Good — invisible to the browser
await new Promise(r => setTimeout(r, 3000));
```
Other tips for maximizing reCAPTCHA scores:
- **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 a fixed fingerprint seed** (`--fingerprint=12345`) 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:
```javascript
await page.type('#email', 'user@example.com', { delay: 50 });
```
- **Minimize `page.evaluate()` calls** before the reCAPTCHA check fires — each one sends CDP traffic
**New update broke something? Roll back to the previous version**
When auto-update downloads a newer binary, the previous version stays in `~/.cloakbrowser/`. Point `CLOAKBROWSER_BINARY_PATH` to the older cached binary:
```bash
# Linux
export CLOAKBROWSER_BINARY_PATH=~/.cloakbrowser/chromium-146.0.7680.177.4/chrome
# macOS
export CLOAKBROWSER_BINARY_PATH=~/.cloakbrowser/chromium-145.0.7632.109.2/Chromium.app/Contents/MacOS/Chromium
# Windows
set CLOAKBROWSER_BINARY_PATH=%USERPROFILE%\.cloakbrowser\chromium-146.0.7680.177.4\chrome.exe
```
## Links
- 🌐 [Website](https://cloakbrowser.dev)
- 🐛 [Bug reports & feature requests](https://github.com/CloakHQ/CloakBrowser/issues)
- 📦 [PyPI (Python package)](https://pypi.org/project/cloakbrowser/)
- 📖 [Full documentation](https://github.com/CloakHQ/CloakBrowser#readme)
- 📧 Contact: cloakhq@pm.me
## License
- **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).
Use against financial, banking, healthcare, or government authentication systems without authorization is expressly prohibited.