Nightlight is a free and open-source software for PC by an indie developer named Walter Imaican. It is a utility tool that provides users with a system tray icon that they can use to easily switch between the built-in light and dark themes found on the Windows operating system.

The dark theme option was a long-requested feature that was finally implemented on Windows 10. It allowed users to switch to it via system settings. Nightlight simplifies the process by letting users change themes directly from their system tray, removing the need to go through various settings and submenus.

How do I use Nightlight?

Using Nightlight is simple and straightforward. Once you've downloaded it, extract the zip file and run the RUN_ME.bat file to begin installation. Its program icon will appear in your system tray afterward. To start using it, left-click on the icon to switch between light and dark themes right away. Meanwhile, a right-click will bring up a contextual menu for you.

From the context menu, you can manually select between light and dark themes, as well as access the settings menu. Hover on it and two more options will appear for you. The first one is to apply the theme to Apps, Explorer, and System. The second is for your Start Menu & Taskbar—you can select either one or both at the same time.

Do note that you will need to have .NET runtime installed before you can install and use Nightlight, but aside from that single requirement, you'll be good to go. One minor hassle that arises from using it, though, is when you try to do an update; you'll need to uninstall the previous version first before you can install a newer version.

Switch themes on the fly

All in all, Nightlight is a simple yet convenient tool for seamlessly switching between Windows' light and dark themes via your system tray. It will especially come in handy when you need to change to a dark theme for nighttime work and such. It gets the job done without any fuss. No more, no less.