Thank you for installing f.lux

f.lux automatically warms up your computer’s screen colors at sunset and returns them to normal at sunrise.

You can change colors, location, and other settings from the f.lux menu.

f.lux menu

The f.lux menu is always located to the left of your system clock.

Some tips for getting started

  1. Set your location: f.lux works a lot better if it knows exactly where you are (we make a guess, but it’s not always good.)
  2. Adjust f.lux’s color settings so it looks as warm as you like it.
  3. Expand your color range so you can try even warmer colors at night. (Note: to do this, you need Administrator access plus a reboot, but it’s really worth it.)
  4. Disable f.lux to edit pictures: Alt-End.
  5. Visit our support page:

New in this version

If you’ve used f.lux before, this version now has these changes:

  • Expanded color temperature settings, down to 2700K, and some presets lower than that, down to 1200K.
  • Display warms up as your backlight dims (works with laptops)
  • Movie mode
  • Disable until sunrise
  • A simple control for Philips Hue lights
  • Hotkeys to dim your screen (Alt-PgUp, Alt-PgDn), so desktop users can dim too, and a hotkey to disable (Alt-End)

More about f.lux

Computer screens, tablets and mobile phones emit full spectrum light around the clock, just like the sun. Exposure to blue light at the wrong time of day can keep you awake later and interfere with the quality of your sleep. f.lux tries to help this by removing blue and green light to help you wind down in the evenings.

It can take a few days to get used to the new colors at night, so we recommend setting the night-time colors in f.lux to whatever feels good to your eyes. After a few days with f.lux, experiment with the settings to warm things up a little more and find which color works best for you. Our default setting of 3400K on Windows removes about 3/4 of the blue and about half of the green light. You can remove even more alerting light by choosing “Expand color range” to unlock deeper colors in Windows (in the “Lighting at night” menu).

Thank you for trying f.lux! We are always working to incorporate the newest research into our software. We’d love to hear what you think.

Copyright f.lux Software LLC 2008-2020