diff --git a/django/contrib/admindocs/views.py b/django/contrib/admindocs/views.py
index 110a91f318..55960cfec5 100644
--- a/django/contrib/admindocs/views.py
+++ b/django/contrib/admindocs/views.py
@@ -264,7 +264,7 @@ def template_detail(request, template):
         else:
             site_obj = GenericSite()
         for dir in settings_mod.TEMPLATE_DIRS:
-            template_file = os.path.join(dir, "%s.html" % template)
+            template_file = os.path.join(dir, template)
             templates.append({
                 'file': template_file,
                 'exists': os.path.exists(template_file),