WhatRuns: find out in one click what technologies a website runs on

WhatRuns is first and foremost for the curious. You land on a fast website, a polished online store or a well-designed form, you click, and within two seconds you know whether it runs on WordPress or Next.js, which tool measures its audience and which font gives it that look. For a developer, a web integrator or an agency salesperson preparing for a meeting, that quick look is often enough, and it costs nothing.

Fundamentally, the extension is comfortable with what can be seen in the browser: JavaScript frameworks, analytics scripts, chat widgets, WordPress plugins. It is much less so with everything else. Results can be incomplete, a version can be misread, and the panel sometimes gets stuck loading or shows up empty. It is best treated as a clue: before stating in black and white in an audit that a site uses a given tool, checking the source code or a second detector is the prudent move.

It also quickly shows its limits once you go beyond one site at a time. No export, no list of sites using a technology, no history and no API: for prospecting or market research, you need a database such as BuiltWith or Wappalyzer’s paid plans. Privacy calls for a caveat. Like every tool of its kind, the extension asks for access to every page you visit, and its very discreet publisher may receive code snippets from them. Nothing unusual for this type of tool, but best avoided on a machine that handles sensitive internal applications.