Built by thejayant

Free website inspector

Its analytics and tag setup, the tech stack and fonts it’s built with, and whether AI built it. Read from the public files every browser downloads: free, no login, nothing stored.

Type a website, a tag ID or a question. Press Ctrl K on any page to search.

Next.jsReactVue.jsSvelteAstroNuxtRemixAngularGatsbyViteTurbopackwebpackTypeScriptTailwind CSSshadcn/uiRadix UIMaterial UIBootstrapSassGSAPFramer Motionthree.js
WordPressWebflowFramerShopifyWixSquarespaceGhostSanityContentfulStrapiVercelNetlifyCloudflareFastlyGoogle AnalyticsGoogle Tag ManagerMeta PixelSegmentHotjarStripeSupabaseSentry

How it works

Oneaddressin. Everythingout.

your-competitor.com
GA4

14events

  • page_view
  • sign_up
  • purchase
Tag Manager

38tags

  • 9 destinations
  • 4 paused
  • 2 custom HTML
Meta Pixel

82/ 100

  • 6 codeless rules
  • Advanced matching
  • CAPI gateway
Tech stack

23technologies

  • Next.js 16
  • React 19
  • Vercel
Typography

3typefaces

  • Sora · Indian Type Foundry
  • Inter · Rasmus Andersson
  • JetBrains Mono
AI check

12% AI

  • Hand-built
  • No builder traces
  • High confidence
Detect AI-built sitesNewAI Website DetectorWas this site built with AI?Tech stack, fonts & designSite DNASee how any website is builtGoogle Analytics 4GA4 CheckerSee any site's Google Analytics 4 setupGoogle Tag ManagerGTM ViewerOpen any Google Tag Manager containerFacebook / Meta PixelMeta Pixel CheckerDecode any Facebook / Meta PixelSegment CDPSegment InspectorMap any Segment stack
230technologies recognized
16AI builders and agents detected
0logins, installs or stored scans

Free & independent

Keep TagSpy free for everyone

No ads, no accounts, nothing tracked. TagSpy is built and paid for by one person. If it saved you an afternoon, a coffee helps cover:

  • Servers and the database
  • Real cloud browsers for every deep scan and AI check
  • New detectors for the next wave of AI builders
Buy me a coffeeTakes a minute · no account needed

Why TagSpy

Everything a website shows the world, in one place

Every website sends its analytics tags, tag manager container, pixels and code to every visitor's browser. TagSpy reads those public files and turns them into clear reports, so marketers, developers and analysts can audit a site, learn from a competitor or debug their own setup in seconds.

Tracking audits

GA4 events and key events, every tag and trigger in a GTM container, Meta Pixel rules and Segment destinations.

Tech stack

Frameworks, CMS, hosting, animation libraries, fonts and design tokens, read from the site's own files.

AI detection

How likely it is that a site was built with Lovable, Bolt, v0, Replit or a coding agent, with the evidence.

Private by design

Only public responses are read. Reports live in your tab and are never stored on our servers.

How it works

  1. 01

    Enter a website or an ID

    Any address works, or a GA4 Measurement ID, GTM container ID, pixel ID or Segment write key.

  2. 02

    We read the public files

    The same HTML, scripts and configurations your browser downloads when you visit.

  3. 03

    Get a clear report

    Plain-language findings, the evidence behind each one, and exports where they help.

Questions

Is TagSpy free?

Yes. Every inspector is free and needs no account. The AI Website Detector includes one free check per person, because each check runs a real browser in the cloud.

Is it legal to inspect another website's tags?

TagSpy reads only what a website publicly sends to every visitor: its HTML, JavaScript and the tag configurations Google, Meta and Segment serve. Nothing private is accessed and no account is used.

Do you store the sites I check?

No. Reports exist only in the response to you and in your browser tab. Nothing about the sites you check is kept on our servers.

What can I use TagSpy for?

Auditing your own analytics before a launch, checking what a client or competitor tracks, finding the GTM container behind a site, identifying the fonts and framework a site uses, and checking whether a site was built with AI.