Why check what theme a Drupal site is running
Drupal remains a common choice for government agencies, universities, and large media organizations that need a content management system built for scale and access control. Its themes are less commercialized than WordPress's or Shopify's, which makes seeing exactly which theme a given .gov, .edu, or enterprise site runs genuinely informative — it's rarely obvious just by looking.
How Drupal theme detection actually works
Drupal themes declare themselves through an .info.yml manifest file and a predictable asset path — custom themes typically live under /themes/custom/<theme-name>/. The Websites Detector scans the site's stylesheet references for this pattern to extract the active theme's name directly from the URL structure Drupal itself generates.
What you can do with the results
For agencies and developers, this is a quick way to see what a comparable organization built their site on before scoping a similar project. For anyone auditing their own Drupal install's public footprint, it confirms exactly what a visitor — or a competitor — can see about your stack from the outside.
A note on limitations
Detection works across Drupal 7 through 10, but sites using entirely custom, undeclared theming setups outside Drupal's standard conventions may not expose a detectable theme name.