See any website's tech stack as you browse
Open a page and the TechnologyChecker icon shows how many technologies it found. Click it for the full list, grouped by category. Free, no account.
What it detects.
About 7,000 technologies in 108 categories: content management systems, ecommerce platforms, analytics and tag managers, JavaScript frameworks and libraries, payment providers, CDNs, fonts, A/B testing and chat widgets.
Runs on the page you are viewing
Detection happens in your browser as each page loads, from the markup, scripts, cookies and response headers the page already sent you.
Grouped by category, with versions
Results are listed by category, and show the version number wherever the site exposes one.
22 languages
The interface follows your browser language, from English and German to Japanese, Korean and Turkish.
Extension or full lookup?
The extension answers “what is this page running?” for the site in front of you. When you need more than the front end, or more than one site, use the website technology lookup or browse the companies using each technology.
| Extension | technologychecker.io | |
|---|---|---|
| Technologies checked | About 7,000 | 40,000+ |
| Where it looks | The page open in your browser: markup, scripts, cookies, headers | The page plus DNS, certificate transparency logs and server-side signals |
| History | What is on the page right now | The date each technology was first detected on the site |
| Company data | None | Industry, headcount, country and verified contacts |
| Lists | One site at a time | Every company using a technology, filterable and exportable |
How each signal layer works is documented on the methodology page.
Questions.
Is the TechnologyChecker extension free?
Yes. It is free to install and use, and it does not need an account. Lookups you run on technologychecker.io itself are covered by the free plan's 100 lookups a month.
How many technologies does the extension detect?
About 7,000 technologies in 108 categories, from content management systems and ecommerce platforms to analytics, tag managers, JavaScript frameworks and CDNs.
Why does the website lookup find more than the extension?
The extension can only see what your browser loads on the page you are viewing. The lookup on technologychecker.io also reads DNS records, certificate transparency logs and server-side signals, and checks across 40,000+ technologies, so it finds email providers, hosting and backend tools that never appear in the page itself.
Which browsers does it work in?
Chrome, and Chromium-based browsers that install extensions from the Chrome Web Store, such as Brave and Microsoft Edge. The interface is available in 22 languages.
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