Enable W10’s Dark Theme

How to Automatically Enable Windows 10’s Dark Theme at Night

by Chris Hoffman 

Windows 10’s dark app mode is easier on the eyes at night, but there’s no easy option to automatically enable it at night—unlike macOS Mojave’s dark theme. Instead, you can automatically turn it on and off with scheduled tasks.

The “Night Light” feature that adjusts the color shade of your screen can automatically enable itself at night and disable itself during the day, but there’s no similar built-in option for dark mode. To set up a schedule for dark mode, you’ll be creating two tasks in Windows’ Task Scheduler app—one that activates dark mode at night, and another that turns it off in the morning.

If you like this, you may also want to change Windows 10’s wallpaper based on the time of day.

Create the Dark Theme Task

First, we’ll create a scheduled task that switches to the dark theme at night.

Launch the Task Scheduler by opening the Start menu, searching for “Task Scheduler,” and then pressing Enter to launch it.

Click Action > Create Basic Task.

Type “Switch to Dark Theme” or another descriptive name into the Name box. Click “Next” to continue.

Select the “Daily” trigger, and then click the “Next” button.

Enter the time when you want the dark theme to enable itself. For example, if sunset is around 9 p.m. in your time zone, you could enter 9 p.m. here.

Ensure that the “Recur every” option is set to “1 days” and then click “Next” again.

Select the “Start a Program” action, and then click the “Next” button.

Type ” reg ” into the Program/script box, and then copy-paste the following line into the “Add arguments” box:

add HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Themes\Personalize /v AppsUseLightTheme /t REG_DWORD /d 0 /f

Click “Next” to continue.

Enable the “Open the Properties dialog for this task when I click Finish” option, and then click the “Finish” button.

Task Scheduler creates your new task, and then opens a window showing additional options. Switch over to the “Conditions” tab, and then disable the “Start the task only if the computer is on AC power” option.

This ensures that the task works normally even if you’re using a laptop on battery power.

Switch to the “Settings” tab, and then enable the “Run task as soon as possible after a scheduled start is missed” check box.

This ensures that the task runs—and the dark theme is applied—even if your computer is asleep or powered off at the time it was scheduled to run.

Click “OK” to finish configuring the task.

You’ll find your task in the “Task Scheduler Library” folder. You can confirm the task works properly by right-clicking it, and then selecting the “Run” command. The dark theme should automatically be enabled.

Create the Light Theme Task

To finish this process, you’ll need to create a second scheduled task that automatically enables light mode during the day. The second task will be similar to the first task, but with a different name, time of day, and command.

Once again, click Action > Create Basic Task.

Name the task “Switch to Light Mode” or something else descriptive, and then click the “Next” button.

Select the “Daily” trigger, and then click “Next” again.

Enter the time when you want the light them to enable itself. For example, if sunrise is at 5:30 a.m. in your location, you might enter 5:30 a.m.

Ensure the “Recur every” option is set to “1 days” and then click the “Next” button.

Select the “Start a program” action, and then click “Next” again.

Type ” reg ” into the Program/script box, and then copy-paste the following line into the Add arguments box:

add HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Themes\Personalize /v AppsUseLightTheme /t REG_DWORD /d 1 /f

Click “Next” to continue.

Enable the “Open the Properties dialog for this task when I click Finish” check box, and then click the “Finish” button.

In the properties window that opens, switch over to the “Conditions” tab, and then disable the “Start the task only if the computer is on AC power” check box.

On the “Settings” tab, activate the “Run task as soon as possible after a scheduled start is missed” check box.

This ensures that the task will run and the light theme will be applied when you wake or boot your computer, even if that’s after 5:30 a.m. or whatever other time you chose.

Click “OK” to finish configuring the task.

You’ll now find both tasks in the “Task Scheduler Library” folder. You can confirm the new task works properly by right-clicking it, and then selecting the “Run” command. The light theme should automatically be enabled.

And now, you’ve got your dark and light themes set to a schedule. Dark mode should automatically turn on at whatever time in the evening you set, and should turn off again in the morning.

How to Change the Scheduled Times

You can return to Task Scheduler anytime to change when dark mode enables or disables itself (which you’ll likely need to do as the seasons change). To do so, just locate the tasks in the “Task Scheduler Library” folder. Double-click a task, switch to the “Triggers” tab of its properties window, click the “Edit” button, and then enter your new desired time. Click “OK” twice to save your changes.

And then just repeat this process for the other task.

How to Remove the Scheduled Tasks

To stop toggling the dark theme on and off on a schedule, return to the “Task Scheduler Library” folder and locate the tasks you created. Right-click each and click “Disable” or “Delete.”

Warning: Don’t disable, delete, or edit any of the Windows system tasks that appear here or you could cause problems with your computer. It’s safe to edit and delete tasks you created yourself, however.

If you think you might use the tasks again in the future, definitely disable rather than deleting them. When disabled, tasks don’t consume any resources.

What About Microsoft Edge?

We also have a command that toggles Microsoft Edge’s dark theme on and off. Unfortunately, while you can flip this switch in the registry, this setting won’t be applied immediately while Edge is running. It only takes effect when you close and reopen Edge, which kind of defeats the point.

However, if you want to try this anyway, go for it. First, head into Task Scheduler and find the task you created to turn on dark mode (we named ours “Switch to Dark Theme” earlier). Double-click the task to open its properties window, switch to the “Actions” tab, and then click the “New” button to create a new action.

Type ” reg ” in the Program/script box, and then copy-paste the following line into the Add arguments box:

add "HKCU\SOFTWARE\Classes\Local Settings\Software\Microsoft\Windows\CurrentVersion\AppContainer\Storage\microsoft.microsoftedge_8wekyb3d8bbwe\MicrosoftEdge\Main" /v Theme /t REG_DWORD /d 1 /f

Click “OK” twice to continue.

Now, double-click the “Switch to Light Theme” task you created (or whatever you called it) to open its properties window. Switch to the “Actions” Tab, and then click the “New” button.

Type ” reg ” in the Program/script box, and then copy-paste the following line into the Add arguments box:

add "HKCU\SOFTWARE\Classes\Local Settings\Software\Microsoft\Windows\CurrentVersion\AppContainer\Storage\microsoft.microsoftedge_8wekyb3d8bbwe\MicrosoftEdge\Main" /v Theme /t REG_DWORD /d 0 /f

Click “OK” twice to continue.

Now, whenever the scheduled task triggers, Edge’s theme setting is also changed—but if Edge is already open, you’ll have to close and reopen it to see the new theme.

Of course, you can always manually change the Edge theme from Menu > Setttings > Choose a theme without relaunching Edge.