diff --git a/frontend/src/Styles/Themes/index.js b/frontend/src/Styles/Themes/index.js
index 02068cc4c..d93c5dd8c 100644
--- a/frontend/src/Styles/Themes/index.js
+++ b/frontend/src/Styles/Themes/index.js
@@ -1,7 +1,11 @@
 import * as dark from './dark';
 import * as light from './light';
 
+const defaultDark = window.matchMedia('(prefers-color-scheme: dark)').matches;
+const auto = defaultDark ? { ...dark } : { ...light };
+
 export default {
+  auto,
   light,
   dark
 };
diff --git a/src/NzbDrone.Core/Configuration/ConfigFileProvider.cs b/src/NzbDrone.Core/Configuration/ConfigFileProvider.cs
index d379ad698..2b3106e21 100644
--- a/src/NzbDrone.Core/Configuration/ConfigFileProvider.cs
+++ b/src/NzbDrone.Core/Configuration/ConfigFileProvider.cs
@@ -198,7 +198,7 @@ public AuthenticationType AuthenticationMethod
 
         public string LogLevel => GetValue("LogLevel", "info").ToLowerInvariant();
         public string ConsoleLogLevel => GetValue("ConsoleLogLevel", string.Empty, persist: false);
-        public string Theme => GetValue("Theme", "light", persist: false);
+        public string Theme => GetValue("Theme", "auto", persist: false);
         public string PostgresHost => _postgresOptions?.Host ?? GetValue("PostgresHost", string.Empty, persist: false);
         public string PostgresUser => _postgresOptions?.User ?? GetValue("PostgresUser", string.Empty, persist: false);
         public string PostgresPassword => _postgresOptions?.Password ?? GetValue("PostgresPassword", string.Empty, persist: false);
diff --git a/src/NzbDrone.Core/Localization/Core/en.json b/src/NzbDrone.Core/Localization/Core/en.json
index 76fe5b98f..f3b85e496 100644
--- a/src/NzbDrone.Core/Localization/Core/en.json
+++ b/src/NzbDrone.Core/Localization/Core/en.json
@@ -928,7 +928,7 @@
   "SettingsShowRelativeDates": "Show Relative Dates",
   "SettingsShowRelativeDatesHelpText": "Show relative (Today/Yesterday/etc) or absolute dates",
   "SettingsTheme": "Theme",
-  "SettingsThemeHelpText": "Change Application UI Theme, Inspired by Theme.Park",
+  "SettingsThemeHelpText": "Change Application UI Theme, 'Auto' Theme will use your OS Theme to set Light or Dark mode. Inspired by Theme.Park",
   "SettingsTimeFormat": "Time Format",
   "SettingsWeekColumnHeader": "Week Column Header",
   "SettingsWeekColumnHeaderHelpText": "Shown above each column when week is the active view",