Ruby on Rails
Ruby on Rails is a server-side web application framework written in Ruby under the MIT License.
About
Ruby on Rails is a server-side web application framework written in Ruby under the MIT License.
Categories: Web frameworks
Quick facts
How we detect Ruby on Rails
Each signal alone is rarely conclusive — Sourcemap Explorer cross-references all of them and weights by confidence. You can reproduce any of these checks yourself in Chrome DevTools.
Server-side fingerprint: the response header reveals the technology behind the page. Visible in DevTools → Network → response headers.
Server: mod_(?:rails|rack)
X-Powered-By: mod_(?:rails|rack)
Cookies set by the platform. Visible in DevTools → Application → Cookies.
_session_id
<meta> tag injected into the document. Visible by viewing the page source.
<meta name="csrf-param" content="^authenticity_token$">
Window-level global the technology installs on page. Reproducible by typing the path into the DevTools console.
window.ReactOnRails
window.__REACT_ON_RAILS_EVENT_HANDLERS_RAN_ONCE__
window._rails_loaded
Script URL pattern. Typically a CDN host or chunk path that ships with the technology.
/assets/application-[a-z\d]{32}/\.jsImplies
When Ruby on Railsis detected, Sourcemap Explorer also marks the following technologies as present (Wappalyzer's implies graph).
FAQ
How do I check if a website is using Ruby on Rails?
Open the page in Chrome, click the Sourcemap Explorer toolbar icon, and read the Stack tab. The popup matches Ruby on Rails's fingerprint signals (response headers, asset URL prefixes, runtime globals, sourcemap paths) and flags it whenever any combination is found. The same checks can be reproduced manually in DevTools — see the "How we detect" section above.
What Ruby on Rails version can Sourcemap Explorer detect?
Ruby on Rails ships as a hosted web frameworks rather than a bundled npm package, so version-specific detection isn't always possible. Where the platform leaks a version in response headers (`X-Powered-By`, `Server`, generator meta tags) we surface it; otherwise we report presence only.
Where can I read more about Ruby on Rails?
Official site: https://rubyonrails.org. For Sourcemap Explorer's detection guide, see the deep-dive link below or the related guides in the cross-link section.
Detected by Sourcemap Explorer
Open the popup on any page running Ruby on Railsand you'll see the exact version pulled from the bundled package.json when sourcemaps are exposed.