Automating Chrome with CDP instead of paid browser tools

When I need full browser control without paying for hosted automation, I attach directly to my own Chrome with the DevTools Protocol. It keeps me in control of cookies and extensions, works on Windows plus WSL, and costs nothing.

Why this approach

• Free and local: no paid browser automation services.
• Uses your real Chrome: same cookies, extensions, profiles.
• Works from WSL to Windows Chrome with a small firewall rule.

One-time setup

1. Close Chrome.
2. Launch Chrome with remote debugging and a dedicated profile:

Start-Process "C:\Program Files\Google\Chrome\Application\chrome.exe" -ArgumentList "--remote-debugging-port=9222 --remote-debugging-address=0.0.0.0 --user-data-dir=C:\temp\chrome-cdp --no-first-run --no-default-browser-check"

1. Allow the port on Windows so WSL can reach it:

netsh advfirewall firewall add rule name="Allow CDP 9223" dir=in action=allow protocol=TCP localport=9223
netsh interface portproxy add v4tov4 listenaddress=0.0.0.0 listenport=9223 connectaddress=127.0.0.1 connectport=9222

1. Verify JSON is reachable:

• In Chrome: http://localhost:9222/json/version
• From WSL: curl http://<windows-ip>:9223/json/version

Connect from Node with Playwright

const { chromium } = require('playwright');
(async () => {
  const browser = await chromium.connectOverCDP('http://<windows-ip>:9223');
  const context = browser.contexts()[0] || await browser.newContext();
  const page = await context.newPage();
  await page.goto('https://example.com');
  // do work here
})();

Practical automations

• Export bookmarks: read the Chrome Bookmarks file and emit Markdown.
• Scrape YouTube Watch Later: open the playlist via CDP, grab titles/links/durations.
• Capture product screenshots: drive your own logged-in session for store assets.
• Restore sessions: keep --user-data-dir dedicated so your tabs and cookies persist between runs.

Security and hygiene

• Never share secrets. Keep env keys out of automation logs.
• Bind to your LAN IP and use the firewall rule so only your machine can reach CDP.
• Use a dedicated user data dir to avoid your personal profile leaking into scripts.
• Close CDP when idle by quitting that Chrome instance.

When to use this vs headless

• Use CDP when you need your real session, extensions, or graphical flows.
• Use headless chromium.launch() when you want a clean sandbox and reproducible runs.

Checklist to run it anytime

• Launch Chrome with the CDP shortcut (includes the flags above).
• Confirm JSON at /json/version.
• Run your Playwright script against http://<windows-ip>:9223.
• Keep secrets out of logs and repos.

Reuse across channels

• Blog: publish this guide as-is.
• X/LinkedIn: share the key commands and why it beats paid browser services.
• Reddit: post in automation or self-hosted communities with the setup steps and security tips.