diff --git a/CHANGELOG.md b/CHANGELOG.md
index 705a66a95d..7b15caca3b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,11 @@
+## Unreleased
+
+### Added
+
+- add `dev_tools_ui` in `<script id="_dash-config" type="application/json">`,
+  so renderer can know if it should enable the UI. [#676](https://github.com/plotly/dash/pull/676)
+
+
 ## [0.40.0] - 2019-03-25
 ### Changed
 - Bumped dash-core-components version from 0.44.0 to [0.45.0](https://github.com/plotly/dash-core-components/blob/master/CHANGELOG.md#0450---2019-03-25)
diff --git a/dash/dash.py b/dash/dash.py
index 040152f29b..10364839e4 100644
--- a/dash/dash.py
+++ b/dash/dash.py
@@ -237,7 +237,8 @@ def _handle_error(_):
             'hot_reload': False,
             'hot_reload_interval': 3000,
             'hot_reload_watch_interval': 0.5,
-            'hot_reload_max_retry': 8
+            'hot_reload_max_retry': 8,
+            'dev_tools_ui': False,
         })
 
         # add a handler for components suites errors to return 404
@@ -328,7 +329,8 @@ def serve_layout(self):
     def _config(self):
         config = {
             'url_base_pathname': self.url_base_pathname,
-            'requests_pathname_prefix': self.config['requests_pathname_prefix']
+            'requests_pathname_prefix': self.config.requests_pathname_prefix,
+            'dev_tools_ui': self._dev_tools.dev_tools_ui,
         }
         if self._dev_tools.hot_reload:
             config['hot_reload'] = {
@@ -1227,6 +1229,8 @@ def enable_dev_tools(self,
         debug = debug or _configs.get_config('debug', None, env, debug,
                                              is_bool=True)
 
+        self._dev_tools.dev_tools_ui = debug
+
         self._dev_tools['serve_dev_bundles'] = _configs.get_config(
             'serve_dev_bundles', dev_tools_serve_dev_bundles, env,
             default=debug,