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Captcha bypass tutorials

How to Find and Verify the Funcaptcha Blob Parameter

Hey everyone! If your project runs into Funcaptcha, chances are you’ll need the blob parameter. Good news—it’s easier to find than you think! Let’s break down how to locate it and make sure everything’s set up right.

🔍 Where to Find the Blob Parameter

1. Using the Network Tab (Easiest Method)

  1. Open Developer Tools (F12 or Ctrl+Shift+I).

  2. Go to the Network tab.

  3. In the filter, type: fc|arkose|enforcement.

  4. Look for a request named something like enforcement.abc123... or fc/api.

  5. Click it → Preview tab → search for the "blob" field.

🔹 Example blob:

"blob": "B7A24B7D-15EF-41...long_string...D3F5"

2. Via Console (If Captcha Is Already Loaded)

  1. Open the Console (F12 → Console).

  2. Paste this:

console.log(document.querySelector('iframe[src*="arkoselabs"]')

.contentWindow.document.body.innerHTML.match(/"blob":"([^"]+)"/)[1]);
  1. If the captcha is present, the console will output your blob!

⚠ Important: Blob Isn’t Always Required!

The blob parameter isn’t needed for every site, but in most cases, it’s critical. If the captcha fails without it—you need it.

🔧 How to Verify Everything’s Correct

1. Use Sandbox Mode

Our service offers a test mode to check your setup without spending funds:

👉 2Captcha Sandbox

How it works:

  1. Send a request with your parameters (websiteURL, publicKey, blob).

  2. If the captcha appears in the worker’s app—everything’s correct! ✅

  3. If not—double-check your parameters (blob might be expired or publicKey incorrect).

2. What If the Captcha Still Fails?

  • Refresh the page to get a new blob (old ones expire).

  • Verify the publicKey (should match the one in <div id="FunCaptcha">).

  • Ensure you’re passing the websiteURL (exact page URL with the captcha).

🚀 What to Do Next with the Blob?

Now that you have the correct blob, you can:

✔ Send it to our API for auto-solving.

✔ Use it in your code for custom integration.

✔ Test in the sandbox to confirm it works.

🆘 Need Help? We’ve Got You!

If you hit a snag or something goes wrong—don’t stress! Our support team is here to help:

✉ Contact us via the feedback form.

📌 Include in your message:

  • The error you received.

  • Your request parameters (no API key!).

  • Screenshots (if possible).

We’ll figure it out and get you back on track—fast!

💡 Key Takeaways

  1. Blob isn’t always needed—but check!

  2. Find it easily via DevTools or console.

  3. Verify correctness in the 2Captcha Sandbox.

  4. If it fails—refresh blob and recheck params.

  5. Stuck? Reach out—we’ll help!

With our service, even tough captchas become easy! 🎉 Happy automating! 🚀