Know the tech behind any website
Stack Spy maps frameworks, analytics, hosting, payments, and more — from a live scan, not a stale list. Built for builders, marketers, and the curious.
Look up any site
Paste a URL or domain. If we already indexed it, you jump straight to its stack. Otherwise we run one scan, then show the page.
Tip: works with or without https:// — we normalize the domain automatically.
Search by technology
Full search →Why Stack Spy
Real detection from live pages and signals — not a stale database snapshot.
Instant scan
Open any site, run the extension, and see categorized technologies in seconds.
Deep categories
CMS, CDN, payments, marketing tags, fonts, frameworks — organized and copy-friendly.
Shareable pages
Every scan gets a public URL under /companies/ for SEO, decks, and Slack.
Featured stacks
A random sample from our index — explore thousands more in Browse.
Start detecting stacks today
Free extension · No account required to scan · Public pages for sharing
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