How do you know what a website is built with?

Platforms leave fingerprints: generator tags, file paths like /wp-content/, script hosts like cdn.shopify.com, cookies and response headers. We read the public page the way a browser does and match those fingerprints.

Can it see WordPress plugins and themes?

Yes, when the page loads their files — we read the theme and plugin folders from the page source and show friendly names for the common ones. Plugins that only run in the admin area aren’t visible to anyone.

Why does it say “likely”?

Some signals are strong (a generator tag), others only suggestive (an image hosted on a CMS’s CDN). We show “likely” when the evidence is suggestive, and list it either way.

Why couldn’t it identify a site?

Fully custom builds, heavy bot protection, or apps that render everything with JavaScript can hide their stack. We only read what’s publicly visible.

Is it free? Are there limits?

Yes — no sign-up, no credit card. Each visitor gets 20 checks per day.

Free tool

What is this website built with?

Enter any website and we'll tell you which CMS or website builder it runs on, the framework behind it, where it's hosted, and the analytics and marketing tags it uses — with the evidence for every answer.

100% free
No sign-up
100+ technologies
WordPress themes & plugins

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How it works

Under the hood in seconds.

Enter a website
Any public site — yours, a competitor’s, or one you admire.
We read the page
Response headers, HTML, scripts and assets — the public fingerprints every platform leaves.
We match signatures
Over 100 technologies across CMS, e-commerce, frameworks, hosting and marketing tools.
See the evidence
Every detection shows how we know, so you can trust the answer.

FAQ

Tech stack detector questions

Outgrown your platform?

We rebuild and migrate sites to fast, modern stacks — Next.js with Sanity or Contentful, or a properly built WordPress — with every URL preserved.

See how migration works

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Enter a website

We read the page

We match signatures

See the evidence

Tech stack detector questions

Outgrown your platform?

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