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f.lux for Mac update

See the changelog.

August 20, 2015

There’s a new f.lux for Mac today. Here’s what’s new:

  1. Dim on disable It’s always been painful to disable f.lux for a color check or late-night design work, so we’ve provided a new option that dims your screen (a lot) when you disable. Check out the “Options” menu for this feature.
  2. Backwards alarm clock For years we’ve wanted an alarm clock that answers the question, “How much sleep will I get if I go to bed now?” So we made a little version of it for f.lux.
  3. Better transitions If you woke up your laptop late in the day, f.lux used to do a very slow transition (as if you were “used to” the orange color). Now it transitions quickly to daylight instead. Also, we’ve tuned up behavior at night and in the morning for “bedtime” mode: the night-time and early morning transitions are longer now.
  4. Expanded daytime settings For users who prefer very warm settings during the day, we’ve made an option that lets the sliders go all the way to 1900K, all the time. We prefer accurate color during the day, but quite a few people have asked for extra control like this. You can find this feature in the Options menu.
  5. Less CPU We made improvements to the profile writer for dual-GPU macs. So this new version should have less impact on those systems especially.
  6. Melanopic lux analysis A new screen analyzer in the About box. Visible easter egg?
Download f.lux for OS X

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p.s. Also check out our measurement project, f.luxometer.

October 25, 2014

There’s an update for Yosemite today.

Dark Mode Option

March 12, 2014

We’re happy to announce a new update to f.lux for Mac today.

This new version has been in progress for a long time. We’re sort of nervous and excited about it, because we tried so many things before we figured it out.

f.lux now works with your actual schedule

  1. f.lux adjusts to your actual day, not just sunrise and sunset.
  2. It looks nice, showing you a visualization of your day.
  3. There are tons of new effects and adjustments.

Your schedule

The new version of f.lux makes a schedule just for you, so you can use a screen that knows when you sleep, as well as when the sun’s up. We found a way to combine your day with sunrise and sunset. Here’s how it looks:

f.lux graph f.lux now shows you when the sun’s up and helps you wind down for sleep.

With the new f.lux, your screen warms up to make things look better at sunset. But then later, around the time you would start feeling sleepy, we do a little more, helping you get to bed on time. We’ve even tried to time this second phase with your body’s natural release of melatonin. You may find you want a more moderate effect at sunset now, because the bedtime setting can be more intense.

It’s really easy to set up, and it looks pretty good too.

What about the sun?

Usually, we try to make things visual and avoid using tons of numbers. But one number stood out so much that we had to put it up front.

How many hours of sunlight could you see with your current schedule?

A healthy circadian rhythm depends on seeing bright light while you’re awake, not just avoiding bright light before bed. Especially if you’re a night owl, this number is a super-interesting way to think about your day, and we hope it’s useful to you too.

Getting started

To have all this new stuff, all you do is tell f.lux when you wake up:

f.lux wake

We suggest some default colors for people in different situations. (For instance, you can now use f.lux if you work the night shift, if you wake up at 3AM, or if you live in Oslo.)

If you need to do color-sensitive work, now you can run at full brightness until just before bed, and then f.lux will wind you down just in time to sleep.

There’s even a way to sleep in on weekends.

Setting up your day

As the day progresses, f.lux will move between its three light settings automatically. But because color perception depends on where you are, it’s kind of hard to predict how you’ll see colors at 11PM while sitting in your office at 1PM. We made this new interface so you can come back a few times (for a day or two) to set f.lux the way you like.

f.lux wake

Improvements, Movies and Darkroom

  1. There’s a Movie Mode to watch movies while preserving shadow detail, skintones, and sky colors. It lasts 2½ hours, longer than most feature films.
  2. There’s a way to disable f.lux until sunrise.
  3. There’s even a super-red mode we call Darkroom.
  4. We’ve reworked all animations to make them smoother and cause less impact on your Mac.
  5. Also added a way to disable f.lux by app. (The “working late” preset works ok for almost everyone, but this is some extra color-accuracy insurance.)


  • v36.4: fixes issues with El Capitan
  • v36.1+: fixes issues with backlight fading, “dark theme” bugs
  • v36: adds Dim on Disable, Backwards alarm clock, improved transition timing, expanded daytime settings, and some experimental melanopic response data
  • v34.3: Fixes a tiny (but annoying) bug that would occasionally disable f.lux briefly at midnight if you had “sleep in on weekends” turned on.
  • v34.2: Fixes bug that enabled a new Yosemite feature on some older machines. Thanks for help debugging!
  • v34.1: Adds color profile for external “HDTV” displays, and fixes a small bug with “disable until morning”.
  • v34: Adds the ability to make a system profile to fix “flashing” on dual-GPU Macs when they switch. This feature is diabled on single-GPU machines. Adds improved location accuracy, especially for extreme latitudes.
  • v32: Fixes timing bugs (“Disable until morning” works even if your machine sleeps), improves Darkroom text quality.
  • v31: Dark-mode compatible icon, Dark-mode switching at sunset, fixes some screen-flashing bugs.
  • v30.1: daytime slider goes down to 2700K now, instead of 3400K before
  • v30: notifiers go away after 30 seconds, rounding fixes, UI fixes
  • v29: disable by app (“disable current app”)
  • v28: fixes for multiple displays
  • v27: variable-framerate animations (makes mouse less jerky for long ones)
  • v26: beta

Thanks for using f.lux, and if you need help with the new features, please join us on our support page here: http://justgetflux.com/faq.html.

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