Sitepeel

Free stack checker

What is this website built with?

The framework, hosting, libraries, fonts and colors behind a site.

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What you get

  • Frameworks, site builders and CMS
  • Animation, 3D and UI libraries
  • Fonts, analytics and hosting

Paste a link above to start

Website technology checker

To find out what a website is built with, paste its link into Sitepeel’s free tech stack checker. It names the framework, CMS or site builder, hosting, libraries and analytics, each with the evidence it found, like a script address or a response header. Server code and databases can’t be seen from outside.

What CMS is this website using?

The checker names the CMS or site builder when the page shows its signs: 70 of them, among 344 technologies it knows.

How to find out what a website is built with

  1. Paste the link

    Paste the website’s link and press Check.

  2. See the stack

    Read the framework, hosting, libraries and analytics, each with the evidence for it.

  3. Go deeper

    Look at the fonts and colors, or generate the full DESIGN.md.

Also in the Chrome extension

Tech stack, on the page you have open

The same checks for any tab, including pages behind a login and sites you’re still building. Free with a free account.

FAQ

Questions about the tech stack checker

What is a website technology checker?

A tool that shows the technology behind a website: its framework, site builder or CMS, hosting, libraries, analytics, fonts and colors. Each result comes with the evidence Sitepeel found.

How do I find out what a website is built with?

Paste the link and press Check. You get the framework, hosting and tools, grouped by kind, each with how it was spotted. Our guide covers other ways to check a site’s tech stack.

How is the stack detected?

Sitepeel loads the page and looks for clear signs: framework markers, script and asset addresses, response headers and CSS patterns. Each result shows its evidence.

How do I find out what CMS a site is using?

Paste the link and press Check. It spots site builders and CMS like WordPress, Webflow, Framer, Wix, Squarespace and Shopify, and frameworks like Next.js, when the page shows their signs.

Why is something missing?

Server-side tools, databases and code that never reaches the browser can’t be seen from outside. Some sites also hide or rename their tools.

What about the design?

The fonts and colors come from the same measurements as the DESIGN.md generator. Generate the full DESIGN.md for the complete design system.

Can ChatGPT analyze a website?

ChatGPT can read a page’s text when it browses and guess the stack from it, but it doesn’t load the page and check its scripts and headers, and it rarely shows evidence. This checker does both, for each result.

Is it a free alternative to BuiltWith or Wappalyzer?

For checking one site, yes: no sign-in and no install. BuiltWith and Wappalyzer add lead lists, history and alerts on paid plans. See BuiltWith alternatives compared.