Comparing Night Shift and f.lux

Night Shift and Flux

First released as part of iOS 9.3, Night Shift slowly shifts the color temperature of your screen to be warmer as the evening goes on. Some claim that this may help you sleep better, as blue light is harsher and can disrupt your sleep cycle, but the science is out on that.

I don’t know if it actually doing anything helpful, but I’ve enjoyed Night Shift on my iPhone and iPad over the last year. I often am wrapping up the day one of these two devices pretty close to bedtime, and I find the warmer tones pleasing. It may be the placebo effect, but using up a device without — ahem, watchOS team — is jarring.

With today’s release of macOS Sierra, Apple has added Night Shift to the Mac.

Of course, savvy Mac users have enjoyed a similar effect for years by way of f.lux, a free Mac app that adjusts the color temperature of the Mac’s display based on time. I’ve used it for years, and I find it hard to remember it doesn’t actually ship with a clean install of macOS.

As is the case with any Sherlocked application, f.lux will have a battle on its hands now. However, there are some pretty big differences between the two that may allow f.lux to stick around for many users.

System Requirements

Night Shift is available on the following Macs running macOS 10.12.4 or later:

  • MacBook Air (Mid 2012 or later)
  • MacBook (Early 2015 or later)
  • MacBook Pro (Mid 2012 or later)
  • Mac mini (Late 2012 or later)
  • iMac (Late 2012 or later)
  • Mac Pro (Late 2013)

If you are using an external display, it must be one of these to be work with Night Shift:

  • Apple LED Cinema Display
  • Apple Thunderbolt Display
  • LG UltraFine 5K Display
  • LG UltraFine 4K Display

Update: A bunch of people on Twitter are saying Night Shift works on third-party external displays, so I’m not sure what this is about.

F.lux, on the other hand, can run on a wider range of machines, virtually any external displays and older operating systems. It’s also available for Windows and Linux.


One of my favorite features of f.lux is the ability to disable it based on what application is in the foreground. For example, I have Adobe Photoshop marked as an exception. as f.lux changing the color temperature of my display could cause me problems while editing photographs.

Apple’s Night Shift has no concept of exceptions. If the screen is warmer, it’s warmer for all applications.

Customization & Schedule

At first glance, f.lux and Night Shift offer pretty similar options. However, f.lux generally gives deeper customization options.

Both Night Shift and f.lux can run automatically between sunset and sunrise, based on your location.1 Both can be manually turned on before the appointed time. F.lux can be disabled for an hour or longer from its menu bar app, while Night Shift can be toggled on and off via Notification Center.

You can adjust the warmth of things manually, for instance, in both, but f.lux also exposes a setting for what the temperature should be during the day.

Wrapping It Up

Night Shift, like many other macOS or iOS features, is much simpler than its third-party competition. It will be fine for millions of users, but for those of us who want more control, f.lux will continue to be a good option.

I’m going to give Night Shift a try, but I bet the ability to set apps to be excluded from the warmer tones will lure me back to f.lux pretty quickly.

  1. Location is set manually in f.lux, making traveling a little annoying at times. I assume macOS will just take care of Night Shift in this regard.