I really like f.lux, which is an app that automatically adjusts the display's apparent color temperature according to the time of day and location (so that the temperature is in sync with Sun).

How to set the color temperature manually? I.e. without f.lux?

Sometimes I'd like to have "tungsten" (2700 K) colors during the day or morning, which would require fiddling with the location coordinates in f.lux. Sadly, there's no "manual mode" that I'm aware of.

I'm looking for a OS X native / software based solution, that would allow me to set white point below 4500 °K, which is the minimum that Color Calibrator can set. Is this even possible?

  • 3
    Fellow f.lux user here. Great app. Best I know w/o 3rd party software or using the monitor's buttons would be to go System Preferences > Displays > Color > Calibrate. Use "Expert Mode". However this will only let you take it down to 4500 K. Interested to find out the answer on this one.
    – boehj
    Apr 23, 2011 at 20:23
  • Maybe I don't understand the difficulty, but can't you just set F.lux's daytime slider to 2700? When you say "sometimes", do you mean algorithmically predictable times/dates? If so, then a script would solve your problem. I think it's possible to write a script to force F.lux to a certain daytime temp (or nighttime for that matter).
    – Kelvin
    May 18, 2012 at 4:10

5 Answers 5


This solution requires F.lux to be installed (I assume it's at /Applications/Flux.app).

Create a text file (let's call it flux-day-color) and put it in /usr/local/bin (usr is under "Macintosh HD" and may be hidden).


if [[ ! -z "$1" && "$1" -ge 2700 && "$1" -le 6500 ]]; then
  defaults write org.herf.Flux dayColorTemp -int "$1"
  killall Flux
  open /Applications/Flux.app
  echo "provide a temperature between 2700 and 6500 (rounded to nearest 100)"

In Terminal, run chmod 755 /usr/local/bin/flux-day-color

Now you can run flux-day-color 2700 in Terminal (or in another script) to change the day temperature. Note that the script restarts F.lux so you may see the display jump to 6500 K for a split second before applying your requested temperature.

It's also possible to schedule this to run at predefined intervals, but that's beyond the scope of this answer (and the question).

If you'd rather have a launchable app that can toggle between 2 temperatures,

Open Terminal and run these commands:

cd /Applications/
mkdir -p flux-day-toggle.app/Contents/MacOS
cd flux-day-toggle.app/Contents/MacOS
cat <<END > flux-day-toggle

Now you'll see a greater than sign. Paste this:




cur_val=`defaults read $DOMAIN $KEY_NAME 2>/dev/null`
if [[ -z "$cur_val" || "$cur_val" -eq "$HIGH" ]]; then

defaults write $DOMAIN $KEY_NAME -int $new_val
killall Flux
open /Applications/Flux.app

Wait for the prompt to appear, meaning the file was written. Now the finishing touch:

chmod 755 flux-day-toggle

Now you can launch the new app. You can customize the LOW and HIGH settings to your liking.

  • Here's a bonus tip: a command-line utility to set the display brightness (ie in lieu of the F1 and F2 keys). hints.macworld.com/article.php?story=20090901021817717
    – Kelvin
    May 18, 2012 at 4:32
  • @koiyu: I used your Gist to manually alter F.lux and it has worked well, thank you. However, I now cannot alter the brightness of my screen using the keypad -- is it possible that this is related to your Gist?
    – user27182
    Jul 14, 2015 at 14:48
  • @user27182 Don't think so — at least my external Apple BT keyboard alters brightness normally even when temperature is being adjusted. All the actions the script does is (1) kill f.lux (2) set f.lux preferences (3) re-open f.lux. It's more likely to be related to f.lux or just a random operating system mishap (ie. have you tried turning it off and on again?) Jul 14, 2015 at 14:59
  • 1
    Reposted due to link rot: Had to check this as an accepted answer as I haven't got Nocturne to work on Mavericks. I enhanced your flux-day-color script a bit and created a Gist that can be used to set either/both day and night temperatures (and just using flux-temp 3000, i.e. without options, to change the current display temperature to whatever regardless of the time.) I also found out the minimum Flux temperature is 2300 K, at least in the current version. Sep 19, 2018 at 12:13
  • @JariKeinänen If you switch your killall in your gist to killall -1 Flux, move it to the bottom of the script (where the open command current is), and remove the open command, Flux won't steal focus when the script is run. I'm running it in a cronjob to hopefully prevent burning on my OLED monitor so not losing focus is super handy. Cron for reference: bash flux.sh -l | grep customNightColorTemp | awk '{print $3}' | awk -F\; '{print $1}' | xargs python -c 'import sys; import random; print(min(max(int(sys.argv[1]) + random.randint(-400, 400), 2700), 6500))' | xargs bash flux.sh
    – mbecker
    Dec 8, 2021 at 16:00

When using the Displays section of your System Preferences, if you calibrate it, select show advanced options, one of the windows is this: enter image description here which to me looks like the white points you were looking for, be sure to uncheck "Use native white point" if you want to manually edit it.

  • Great info, thanks. I hadn't had the guts to go through all the steps just for the white point. Sadly, though, the lowest kelvin is 4500-4700 (just closed the window ><). Is there a way to adjust just the white point? (well, I could calibrate different profiles) And how to adjust it below the Calibrator's options? Apr 23, 2011 at 20:31
  • 1
    I found the value hardcoded in /Users/username/Library/Preferences/com.apple.ColorSyncCalibrator.plist, but editing it to a lower value had no effect. I will keep looking. Apr 23, 2011 at 20:37
  • It did have an affect when I logged in and out, I was able to black out my entire monitor, so probably relauching something will reset the value Apr 23, 2011 at 20:41
  • I think I am going to need to ask my own question, something along the lines of what actions are the sys prefs taking after loading that file to tell the mac to activate the change besides changing the file. Apr 24, 2011 at 0:22

Found a possible workaround for those who are interested:

Nocturne by Blacktree

Nocturne preferences

It has a nice amount of options and is completely manual. Downside is it doesn't set apparent color temperature per se, but setting a white tint to RGB(255, 197, 143) has approximately the same effect as setting white point to ≈ 2600 °K (see Kelvin ⇔ RGB table on planetpixelemporium).

  • 1
    d= (◕‿↼ ) Thanks! I found it's latest release on GitHub in both binary and source forms (while a lot of other tools cost money just to install).
    – Top-Master
    May 30, 2021 at 4:28

Open system preferences, go to the Displays panel and choose the Color tab. Press the Calibrate... button and go through the steps. If you turn on expert mode, you will choose the white point using a slider, but if you don't you will get to choose between a few standard values. You can even do this multiple times, saving with a different name each time, and switch between them through the list in the color tab.

  • Sadly, the lowest target white's are somewhere 4500–4700 °K. Do you know how to tune it down to, say, 2700 °K? Apr 23, 2011 at 20:34

A cool way is to let f.lux do the work http://stereopsis.com/flux/ It adjusts your screen colour temp. with the time of the day! Give it a try!

  • 1
    I think you missed the part of his question where he said "without f.lux." Apr 24, 2011 at 14:27
  • oh sorry... I realized it when I just had posted my answer Apr 24, 2011 at 14:30

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