diff --git a/flask_restx/api.py b/flask_restx/api.py
index bda1c0c1..0eefce8d 100644
--- a/flask_restx/api.py
+++ b/flask_restx/api.py
@@ -503,11 +503,11 @@ def endpoint(self, name):
     @property
     def specs_url(self):
         """
-        The Swagger specifications absolute url (ie. `swagger.json`)
+        The Swagger specifications relative url (ie. `swagger.json`)
 
         :rtype: str
         """
-        return url_for(self.endpoint("specs"), _external=True)
+        return url_for(self.endpoint("specs"))
 
     @property
     def base_url(self):