Tools
Browser Extension Detector
Discover which browser extensions websites can detect using fingerprinting techniques. Scans for ad blockers, password managers, crypto wallets, and more.
Scanning for extensions...
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Ad Blockers
Password Managers
Privacy & Security
Crypto Wallets
Productivity & Writing
Developer Tools
How Browser Extension Detection Works
Web Accessible Resources
Some extensions expose images or files that websites can attempt to load. If the resource loads successfully, the extension is installed.
const img = new Image();
img.src = `chrome-extension://${extensionId}/icon.png`;
img.onload = () => console.log('Extension detected!');DOM Injection Detection
Many extensions inject elements into web pages. We can detect these by looking for specific selectors or attributes.
// Grammarly injects a custom element
const hasGrammarly = !!document.querySelector('grammarly-desktop-integration');Global Object Detection
Extensions like crypto wallets inject APIs into the window object that can be detected.
// MetaMask injects window.ethereum
if (window.ethereum?.isMetaMask) {
console.log('MetaMask detected!');
}Behavioral Detection
Ad blockers can be detected by attempting to load known tracking scripts or ad network resources.
// Try loading a known ad script
fetch('https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js')
.catch(() => console.log('Ad blocker detected!'));Privacy Notice
This tool runs entirely in your browser. No data about your extensions is sent to any server. Extension detection is a form of browser fingerprinting that can be used to track users. Brave and other privacy browsers actively work to prevent these detection methods. This tool is for educational purposes to help you understand what websites can potentially detect about your browser.