diff --git a/server.py b/server.py
index ef8d50a2c164c7f2460952851c1a3b5ec1484a30..f5acc7353e028c36a0244ddca93e72a96b8e1f81 100644
--- a/server.py
+++ b/server.py
@@ -323,7 +323,7 @@ def courses():
 		if course['semester'] == '':
 			course['semester'] = 'zeitlos'
 	groupedby = request.args.get('groupedby')
-	if groupedby not in ['title', 'semester', 'organizer']:
+	if groupedby not in ['title', 'semester', 'organizer', 'subject']:
 		groupedby = 'semester'
 	return render_template('courses.html', courses=courses, groupedby=groupedby)
 
diff --git a/templates/courses.html b/templates/courses.html
index 1d0313e4179077a60a9dc0bcd8accc77cd6fd980..9c8ff488b527cdbfa9132c39122d10b6b27ac93d 100644
--- a/templates/courses.html
+++ b/templates/courses.html
@@ -19,8 +19,9 @@
 				</button>
 				<ul class="dropdown-menu dropdown-menu-right">
 					<li><a href="?groupedby=semester">Semester</a></li>
-					<li><a href="?groupedby=title">Veranstaltungen</a></li>
-					<li><a href="?groupedby=organizer">Dozenten</a></li>
+					<li><a href="?groupedby=title">Veranstaltung</a></li>
+					<li><a href="?groupedby=organizer">Dozent</a></li>
+					<li><a href="?groupedby=subject">Kategorie</a></li>
 				</ul>
 			</li>
 		</ul>