diff --git a/src/octoprint/server/api/settings.py b/src/octoprint/server/api/settings.py
index 36efd324..0afb6913 100644
--- a/src/octoprint/server/api/settings.py
+++ b/src/octoprint/server/api/settings.py
@@ -285,7 +285,11 @@ def setSettings():
 					logger.exception("Could not save settings for plugin {name} ({version})".format(version=plugin._plugin_version, name=plugin._plugin_name))
 
 	if s.save():
-		eventManager().fire(Events.SETTINGS_UPDATED)
+		payload = dict(
+			config_hash=s.config_hash,
+			effective_hash=s.effective_hash
+		)
+		eventManager().fire(Events.SETTINGS_UPDATED, payload=payload)
 
 	return getSettings()
 
diff --git a/src/octoprint/server/util/sockjs.py b/src/octoprint/server/util/sockjs.py
index 8e7df023..44b682f8 100644
--- a/src/octoprint/server/util/sockjs.py
+++ b/src/octoprint/server/util/sockjs.py
@@ -13,6 +13,7 @@ import time
 import octoprint.timelapse
 import octoprint.server
 from octoprint.events import Events
+from octoprint.settings import settings
 
 import octoprint.printer
 
@@ -58,8 +59,16 @@ class PrinterStateConnection(sockjs.tornado.SockJSConnection, octoprint.printer.
 		plugin_hash = hashlib.md5()
 		plugin_hash.update(",".join(ui_plugins))
 
+		config_hash = settings().config_hash
+
 		# connected => update the API key, might be necessary if the client was left open while the server restarted
-		self._emit("connected", {"apikey": octoprint.server.UI_API_KEY, "version": octoprint.server.VERSION, "display_version": octoprint.server.DISPLAY_VERSION, "plugin_hash": plugin_hash.hexdigest()})
+		self._emit("connected", dict(
+			apikey=octoprint.server.UI_API_KEY,
+			version=octoprint.server.VERSION,
+			display_version=octoprint.server.DISPLAY_VERSION,
+			plugin_hash=plugin_hash.hexdigest(),
+			config_hash=config_hash
+		))
 
 		self._printer.register_callback(self)
 		self._fileManager.register_slicingprogress_callback(self)
diff --git a/src/octoprint/settings.py b/src/octoprint/settings.py
index d20b56b9..b09d8b82 100644
--- a/src/octoprint/settings.py
+++ b/src/octoprint/settings.py
@@ -544,6 +544,20 @@ class Settings(object):
 		import yaml
 		return yaml.safe_dump(self.effective)
 
+	@property
+	def effective_hash(self):
+		import hashlib
+		hash = hashlib.md5()
+		hash.update(repr(self.effective))
+		return hash.hexdigest()
+
+	@property
+	def config_hash(self):
+		import hashlib
+		hash = hashlib.md5()
+		hash.update(repr(self._config))
+		return hash.hexdigest()
+
 	#~~ load and save
 
 	def load(self, migrate=False):