detectIncognito.js

Efficiently detect Incognito mode & other private browsing modes across most modern browsers.

Shameless plug: Looking for a powerful user tracking and bot detection solution?

Features

• ✅ Incognito detection on Google Chrome
• ✅ Private Window detection on Safari (macOS)
• ✅ Private Tab detection on Safari (iOS)
• ✅ Private Window detection in Firefox
• ✅ InPrivate Window detection on Microsoft Edge
• ✅ InPrivate Window detection on Microsoft Internet Explorer
• ✅ Private Window detection in Brave (see notes)
• ✅ Private Window detection in Opera

Demo

Check out the live demo.

Usage

Get the script from CDN (may be blocked by adblockers—see notes):

<script src="https://cdn.jsdelivr.net/gh/Joe12387/detectIncognito@main/dist/es5/detectIncognito.min.js"></script>

Or install via NPM:

npm i detectincognitojs

import { detectIncognito } from "detectincognitojs";

detectIncognito().then((result) => {
  console.log(result.browserName, result.isPrivate);
});

Supported Browsers

| Browser | Platform(s) | Versions | Notes | |-----------------|-------------|---------------------|-----------------------------------------------------------------------------------------------| | Safari | All | ≤ 18.4 | | | Chromium | All | 50 to 137 Beta | Detection broken by predictable-reported-quota flag (Issue #49) | | Firefox | All | 44 to 138 | | | MSIE | Windows | 11 | Requires Promise polyfill |

Notes

• False positives can occur in certain browser setups or Chrome Guest mode (Issue #21).
• Firefox Container Tabs aren't detected by this.
• The script must run over HTTPS—running locally or via HTTP might fail.
• Brave and uBlock Origin block the CDN; hosting the script yourself avoids this issue.
• An error is thrown if the browser can't be identified.

Similar Projects

• OverpoweredJS – An advanced browser fingerprinting & bot detection solution.

License

Copyright © 2025 Joe Rutkowski
Distributed under the MIT License.