How to Automatically Switch the Brightness of the Windows 10 Screen Each Night

If you spend a lot of time in front of your Windows computer screen, you probably end up every night with tired eyes from your screen. Fortunately, there are some settings in Windows 10 that allow you to mitigate the effects of screen light on your eyes, and one of those settings is Dark Mode.

What is Dark Mode in Windows 10?
Dark mode (which has nothing to do with Night Light simply adding a warm red tint to your screen) lets you select a dark background in some Windows 10 applications. It can only affect specific Windows applications 10, such as the Settings window and the Microsoft Store. Some other applications and programs, including Microsoft File Explorer and Edge, are not affected by dark mode.

To manually activate the dark mode and see how it is, you can go to Settings> Personalization> Colors and under "Select default application mode", select "Dark".

But what if you only want the dark mode at night and you do not want to do it manually every day? The good news is that you can automate it simply by using the built-in Windows 10 task scheduler.

How to automatically activate dark mode at night
1. In the Windows 10 search bar, type Task Scheduler and open the program.
2. In the Task Schedule menu, click Action> Create Basic Task.

3. In the Basic Job Creation Wizard window that appears, type a name for the job (such as Enabling Dark Mode) and click Next.

4. In the next question "When do you want your work to start?", Select "Daily" and click Next.

5. Leave the start date as it is. fill in the time you want to activate the dark mode function and click the Next button. If you have a laptop and travel with it, make sure you select "Time Zone Sync".

6. In the question "What action do you want your task to perform" select "Start Program" and click Next.

7. In the "Program / Script" field, type Reg. In the "Add Names (Optional)" field, copy and paste the following and click Next:

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

8. Click the Finish button.

If your computer is turned off at the time you choose to make the change, Dark mode will not be turned on unless you do the following. Right-click on the new task and select "Properties".
In the dialog that will open, go to the Settings tab and select "Run as soon as possible after skipping" and press the OK button. This way the task will be performed as soon as you turn on your computer and so the dark mode will run.

You can review the settings for each task in the Task Schedule by opening the Task Schedule and then clicking the Task Schedule Library, then finding the task you want to edit (listed in alphabetical order) and right-clicking on it, selecting from the Settings tab.

How to turn off the dark mode automatically during the day
This step is necessary if you want your computer to switch between the two modes. With the first task your computer switches to Dark mode every specific time of night but to return to normal day mode you will also need to program it. This is done by creating a second task, taking the same steps above with the difference that in Step 3 you have to give a different name to the new task (say “Activate Light mode”), in Step 5 you select the time in the morning that you want to activate the light mode function.
Also, in Step 7, in the Program / Script field, type Reg. In the Add Arguments field (optional), copy and paste the following and click Next:

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

Then follow the remaining steps of the first example.

How to edit or delete jobs
If you change your mind and decide that you no longer want to activate dark mode automatically or want to make changes to settings such as activation time, open the Task Scheduler and click on the "Task Schedule Library". After selecting the task you want, right-click on it and select, disable, properties or delete, depending on what you want to do. You can even check "Run" to activate the feature immediately.