What Does This Site Know? Privacy Scanner by Oleg_Che

What does this website know about you? Click the cat 🐱🔍 and get a clear privacy report for the page you are on — in one second, right inside Firefox.

What Does This Site Know? is a free website privacy scanner and tracker detector. It shows which analytics, advertising and social media trackers a site loads, which cookies and browser storage it uses, which third-party domains receive your IP address, and whether the page calls APIs typically used for browser fingerprinting.

Key features

• Privacy Score 0–100 for every website — with a transparent breakdown of every deduction
• Live score badge on the toolbar icon (green / orange / red) — no need to open the popup
• Tracker detector: Google Analytics, Google Tag Manager, Yandex Metrica, Meta Pixel, DoubleClick, Criteo, TikTok Pixel, Hotjar and many more, plus Firefox's built-in tracker classification (Disconnect lists)
• Network requests: first-party vs third-party, unique domains, HTTPS / HTTP, filters by Analytics, Advertising, Social
• Cookie viewer: first-party and third-party (Total Cookie Protection) cookies, session vs persistent, Secure, HttpOnly, SameSite — cookie values are never read
• Browser storage: localStorage, sessionStorage, IndexedDB, Cache Storage, Service Workers
• Browser fingerprinting test: Canvas, WebGL, AudioContext, fonts, WebRTC, screen, timezone — what is available to the page and what the page actually accessed, with a Low / Medium / High risk estimate
• UTM remover / URL cleaner: detects utm_source, utm_medium, utm_campaign, gclid, fbclid, msclkid, yclid and other tracking parameters and opens a clean URL in one click
• Permissions: geolocation, camera, microphone, notifications, clipboard — requested, granted or denied
• "What can the site know": device, browser, language, timezone, screen, referrer, IP visibility
• Security signals: HTTPS, mixed content, third-party iframes, suspicious redirects, insecure forms, external scripts
• Compare two websites side by side, local history of checks
• Export report to JSON, CSV or HTML
• Light and dark theme, tooltips for every technical term (interface in Russian)

Honest by design

The add-on never claims "this site is spying on you". It uses technically correct wording: "analytics service detected", "signals that may be used for fingerprinting", "purpose not determined". A cookie alone is not proof of tracking — it may be used for login, settings or a shopping cart.

Private by design

• All analysis happens locally inside Firefox
• No servers, no accounts, no analytics, no ads, no AI, no API keys
• Your browsing history, URLs, cookies, IP address and reports are never sent anywhere
• History is stored only in your browser and can be cleared with one click

Permissions explained

webRequest — observe (not block) network requests to detect third-party domains and trackers · cookies — list cookie names and flags (not values) · scripting — run a local probe in the active tab · storage — keep your history and settings locally · access to all websites — needed so any site can be analyzed.

Perfect for privacy-conscious users, web developers, marketers and SEO specialists who want to audit trackers, cookies, analytics tags and UTM parameters on any website.

Created by SEO Toolkit — free SEO tools and website audits: https://seotoolkitru.onrender.com/