Laptop user with glasses removed, rubbing eyes

Save Your Eyes with This Free Tool

Humans weren’t designed to look at TVs, computer monitors, and smartphones all day. Now that our lives tend to revolve around these devices, digital eye strain has become a widespread issue. Symptoms of digital eye strain include itchy/burning eyes, blurred vision, or even headaches after using a device.

As an IT professional, eye strain had become a daily occurrence for me. I believed if I could just soften the brightness or shift the color of the screen, my eyes wouldn’t feel so assaulted by it. I also found that my optimal monitor brightness changed throughout the day, depending on the brightness of the room. Messing with my monitor settings didn’t help, so I went looking for a software solution.

Enter F.lux

F.lux is a free, lightweight utility that can control the display “warmth”, and thereby brightness. Corporate site licenses are available for Windows machines, but they are only required if your IT admin wants to control the installation and settings. F.lux is available for Windows, Mac, Linux, iPhone/iPad, and Android. It can be used in one of two ways:

  • Enter your location and the type of lighting you have, and let f.lux adjust your display automatically throughout the day
  • Change the brightness or warmth of the display to a single comfortable setting that remains constant all day. This is what I do since I spend most of my screen time in a room with fluorescent lighting where the time of day does not affect my ambient brightness.

Using F.lux

For the purposes of this article, instructions and screenshots refer to the Windows version of the software. During installation, you will be asked for your location. This information will help f.lux determine the kind of natural light you get and what time it is where you are.

After installing F.lux, you will find it in your taskbar on the bottom-right of your screen. In this image, it is the icon immediately to the right of the arrow:

Screenshot of the taskbar, showing the f.lux icon location

Click the icon to open the tool. Here is how mine looks:

Screenshot showing the f.lux control window with a menu icon in the upper left.

Because I knew I wanted the same warmth/brightness all day, I simply dragged the white button on the slider until the display looked more comfortable to me. The other information on the screen would suggest that the time of day is involved in the settings, but if you look in the upper right, the status is “warm all the time.” This means my setting stays the same all day.

If you want your warmth/brightness to change by time of day, click the orange dot next to the Circadian response percentage. This will convert the single slider into three sliders that can be set independently:

Screenshot showing three sliders labeled daytime, sunset, and bedtime.

After setting the sliders, you can click in the circadian response area to get a time lapse 24-hour preview of how the display will change over the day. If it’s not what you’re looking for, try adjusting again.

The Menu

For most folks, that would be enough configuration to make a world of difference. If you would like to dig deeper and discover more adjustments. If you have smart lighting in your home, you will definitely want to check out the “options and smart lighting” section.

If you use dual monitors like I do, getting both monitors to change can be tricky. If you only have one monitor showing the change, go to Settings>System and try duplicating the monitor display or changing which monitor is primary. Often, changing one of these settings will trigger f.lux to make both displays the same. Afterward, you can revert the settings to the way you had them and both screens should remain matched.

Other Resources

While F.lux is a great tool and using it on all of your devices will definitely reduce eye strain, there are other steps you can take to reduce eye strain, such as wearing blue light blocking glasses. Cornell Cooperative Extension of Rensselaer County has put together a video and an article that offer additional strategies for reducing eye strain. What are your favorite methods for battling eye strain? Let us know in the comments!

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