I'm a fairly nocturnal creature by nature, but life requires me to spend more time during the bright hours of day. I also have a visual impairment which makes it that my eyes take a very long time to adjust to darker situations. In short: I need to be able to easily dim my screen so that using my computer doesn't keep me awake as much and doesn't prevent me from doing other stuff.

Similar questions have been asked before, but I'm still looking for a suitable solution. I will accept both a hotkey based solution–like on most laptops–as a timed one.

Please note:

  • My main monitor lacks simple brightness/contrast controls.
  • f.lux doesn't suit my needs, since it only changes the screen's color temperature.
  • I'd like the solution to work regardless of the make and model of the video card involved.
  • Wearing sunglasses is impractical, since they make it hard to interact with objects around my computer.
  • I always just press <Ctrl><Alt><L> for that... Dec 8, 2010 at 20:19
  • 1
    On which operating system would that be? It doesn't do anything for me here on Windows 7.
    – oKtosiTe
    Dec 8, 2010 at 20:29
  • 1
    Linux. Windows probably uses <Super><Shift><L> or something pretentious like that. Dec 8, 2010 at 20:59
  • 3
    What we really need is something that does this for all those blindingly-bright electronic billboards.
    – Martha
    Dec 9, 2010 at 0:32
  • 1
    I answered below but dimming it never works for me... I always seem to end up back on reddit for some reason
    – Ciaran
    Dec 9, 2010 at 0:39

17 Answers 17


I think I just found the answer to my own question. Better solutions are welcome of course.

With the application Display Tuner I can set the brightness, contrast, color levels and speaker volume for my external monitor. Not the video card, my actual monitor.
It allows me to set hotkeys for separate profiles, lives in the tray (notification area) and is free for non-commercial use.
The main draw is that it only supports monitors that can be controlled through DDC.

Display Tuner screenshot

  • Does it work for changing your brightness?
    – afrazier
    Dec 14, 2010 at 20:22
  • 1
    Sadly, this did not work for me--said my monitor is unsupported. :( Dec 15, 2010 at 10:22
  • 3
    @musicfreak: Yeah, it would have been nice if it fell back to adjusting the video card's settings. For that you could try the (old, but still working) program Gamma Panel, or the nagware PowerStrip.
    – oKtosiTe
    Dec 15, 2010 at 12:06
  • 1
    Sweet, Gamma Panel works. Thanks for the link! Dec 15, 2010 at 22:22
  • 2
    The software has been retired from that website Jun 12, 2013 at 7:55

I just did up a quick console app that will work with Vista+


Source here - you'll be able to build it from Visual Studio Express


brightener 100 //highest
brightener 0 //lowest

You could set it up as a scheduled task if you want to automate it.

I think Linux has a built in command to do this. edit: after googling I found this. Substitute 100 for the brightness you want.

sudo echo –n 100 > /proc/acpi/video/VGA/LCD/brightness

edit: to set up a scheduled task in Windows 7...

  1. Go to Control Panel
  2. Go to Administrative Tools
  3. Open Task Scheduler
  4. Go to Action > Basic Task
  5. Follow wizard
  6. When asked for schedule, enter night time you want to dim light
  7. When asked for the path, enter the path to the unzipped exe above followed by your preferred dim level
  8. Repeat for daytime, changing scheduled time and brightness level
  • @Ciaran: I'm sorry to say that the app simply returns Please enter a number between 1 and 100, no matter what I do.
    – oKtosiTe
    Dec 12, 2010 at 1:31
  • Sorry dude, the extent of the testing I did was making it work. It'll spit "please enter a number between 1 and 100" if it fails for any reason, not just if it doesn't get a proper number. I can post the code up if it helps. The only error I can think of being thrown is class not found which would mean you're not using Vista or Win 7? But you said you are so shrug
    – Ciaran
    Dec 14, 2010 at 20:06
  • No worries. I'd love to see your code, perhaps you could put it on Pastebin? Who knows, maybe I'll learn something. :-) @Ciaran
    – oKtosiTe
    Dec 14, 2010 at 20:42
  • Edited to add source. I changed the code a bit so that it'll give you a proper exception message. You'll need to add a reference to System.Management. If you need more help just let me know.
    – Ciaran
    Dec 14, 2010 at 21:23
  • I'm having the same problem as @oKtosiTe unfortunately. I'll take a look at the source code when I have time and see if I can't figure it out. Dec 15, 2010 at 10:25

Sometimes monitor/laptop's adjust buttons ain't enough.

For Linux:

xcalib -invert -alter # will invert the color under Xorg, xcalib.sf.net says it also supports Windows, I haven't tried.

xrandr's --brightness and --gamma options will also help.


The official ATI driver's Control Panel under Windows enables me to adjust Gamma/Brightness/Contrast, even my laptop doesn't support these via hardware buttons. I believe Nvidia's driver also has these options.


As mentioned in the answer of oKtosiTe (the OP), this could be done via Display Data Channel. Found these software linked on the wikipedia page:


  • ddccontrol: Linux software which uses DDC/CI to control monitors supporting this protocol. (Seems to be not supported and not maintained at this time).


  • softMCCS: Windows software which uses DDC/CI to control monitors supporting this protocol.
  • Nicomsoft WinI2C/DDC: Windows Software Development Kit (SDK) which uses I2C and DDC/CI protocols to control monitors.
  • ScreenBright: Small Windows software which uses DDC/CI to control monitors supporting this protocol.

f.lux v3.10 has additional functionality to control actual brightness using hot-keys Alt+PageDown and Alt+PageUp.

dimming screen with flux

  • This does not answer the question, as flux doesn't use DDC. Dimming with flux in this way has several disadvantages: The mouse cursor stays super bright, you get more color banding, and the monitor uses more energy. forum.justgetflux.com/topic/7150/…
    – LTR
    Jun 9, 2020 at 18:35

I found ClickMonitorDDC from a recommendation on Superuser:

softMCCS from ddc-ci.com allows lots of control but it's too low level technical for regular use.

Just to control brightness and contrast I'm using http://clickmonitorddc.bplaced.net (Windows).

answered Mar 15 '15 at 23:09 aland

Desktop LCD monitor which allows backlight to be controlled in software

ClickMonitorDDC is a portable freeware tool to adjust brightness or contrast of a DDC compatible monitor


It's the most user-friendly application that I've tried.

You can quickly jump to any brightness and contrast number that is a multiple of 5, and then finely adjust.

There are also hotkeys, and command line commands.


b20 c30

Brightness 20 contrast 30.

ClickMonitorDDC also allows you to jump to a volume.

With the default Windows 10 volume control, it's hard to see the exact volume number that you will jump to.

ClickMonitorDDC has 20 volume buttons that are each a multiple of 5, and they go from 0 to 100.

I also tried this recommendation in combination with ClickMonitorDDC:

Flux v3.10 has additional functionality to control actual brightness using hot-keys Alt+PageDown and Alt+PageUp.

answered Jun 25 '14 at 17:25 Karan

Flux is a filter, and it can get you darker than ClickMonitorDDC and your monitor will by themselves.


Useful Answer: Well, for something clickable on screen, there's the Display Brightness Gadget. Also on the page is a command line utility for getting/setting the screen brightness. You can use that with the Task Scheduler or your favorite hotkey tool of choice for timed or hotkeyed modification of your brightness.

Snarky Answer: It's not your monitor's brightness keeping you up, it's the upright position, focusing on a screen, and brain engagement (maybe :-P ) from interacting with your PC keeping up awake.

Snarky Answer #2: Your monitor has a power button -- use it.

  • Snarky answers aside, I also have a visual impairment that makes it very hard for me to adjust to different light levels. Thanks for the suggestions, will give them a try. :-)
    – oKtosiTe
    Dec 8, 2010 at 21:52
  • I'm sorry to say that the gadget nor the command-line utility seem to work on Windows 7.
    – oKtosiTe
    Dec 8, 2010 at 22:02
  • 1
    Both definitely work, I'm using them both on my Windows 7 laptop. Your system must not support software control of the monitor brightness. If it's a desktop system -- most don't. It's possible that updated monitor drivers may enable that feature though.
    – afrazier
    Dec 8, 2010 at 23:26
  • I'll see if updated drivers are available.
    – oKtosiTe
    Dec 9, 2010 at 12:20
  • I already have the latest driver for my monitor. No luck.
    – oKtosiTe
    Dec 10, 2010 at 15:13

f.lux will adjust brightness through out the day to ease eye strain. http://www.stereopsis.com/flux/

  • 8
    It doesn't adjust brigthness, just color temperature (very different things). And it was stated in the question. Read the questions more carefully next time.
    – Greg
    Dec 9, 2010 at 11:33
  • What's great about f.lux, however, is that it at least showed me that what I'm looking for is technically possible. @ScottZ, @Greg
    – oKtosiTe
    Dec 12, 2010 at 1:41
  • 3
    (@oKtosiTe, just for your information: by using @ScottZ, @Greg Greg will not have received a notification for your comment. But ScottZ being the author of this post, @Greg, @ScottZ, or ScottZ, @Greg or even just @Greg would have worked for both... See How do comment @replies work? for the details.)
    – Arjan
    Dec 13, 2010 at 22:38
  • As @Greg said, f.lux, while being a great application, doesn't actually do much in the way of changing the monitor's brightness. I did mention it in my question.
    – oKtosiTe
    Dec 14, 2010 at 21:27

So far RedShift is the only one i can live with. A bit buggy, but it does the trick.

  • Can you add an explanation as to why this addresses the OP's needs? Thanks!
    – bertieb
    Sep 29, 2015 at 20:31

MysticMon has brightness, contrast and color correction and works on multiple monitor systems. It also has hotkey support, monitor reset to factory defaults and can be used to put monitors to sleep via hotkey or command line. Requires Vista or Windows 7 and works on both monitors and laptop LCD displays.


Try PangoBright:

PangoBright is a free "screen dimmer" Windows utility for setting the brightness of your main screen as well as external monitors. You can choose which screens will be set to the selected brightness level.

  • 1
    Care to elaborate at all?
    – random
    May 2, 2011 at 0:45

Mac Brightness Control might help and it's free.

Mac Brightness Control allows you to adjust the brightness level of your Mac (MacBook Pro, MacBook Air, iMac, Mac Pro, Mac Mini) on Microsoft Windows. For instance, a Mac with Windows 7 loaded is too bright for most users, and you can make its screen dimmer with the help of the Mac Brightness Control software.

If the brightness keys on your Mac keyboard are not working properly after you install and restart Microsoft Windows, you can drag the brightness slider in the Mac Brightness Control software to change your screen brightness.

enter image description here

  • 1
    But does it work on regular PCs?
    – oKtosiTe
    Jul 18, 2012 at 7:42
  • Not free anymore :( Jun 20, 2013 at 16:14

I found another alternative. Desktop Lighter. Some features are:

  • Windows only.
  • It lives in the system tray
  • Clicking on the tray icon brings up a simple (but very ugly, IMO) slider which you can slide to change your brightness.
  • If you think clicking on icons is for losers, it has hotkey support:
    • Ctrl + < = reduce brightness.
    • Ctrl + > = increase brightness.
    • I do not see a way to change these hotkeys.
  • It has an option to auto-start with Windows (yes I know you can schedule with the Task Scheduler but this just makes that easier).
  • For anybody seeing this now, I just wanted to point out that this does not play nice with f.lux installed. It causes all sorts of weird, unpredictable behaviour which I cannot seem to find a pattern for (tested on several TVs, monitors and projectors). Jan 20, 2014 at 7:39

I have written a solution to this problem.


You can save your lattitude and longitude to the config file, and then it will vary screen brightness according to sunrise / sunset times at your location.

(Unlike f.lux is actually changes brightness instead of colour tone)


Press Win+X, then adjust the brightnest at the level that you want from the first slidebar. Win+X will launch the Windows Mobility Center, you don't need any external application.

  • The Windows Mobility Center doesn't have a brightness slider on any of my computers. The first slider is for volume.
    – oKtosiTe
    May 2, 2011 at 13:36
  • Maybe i assume that this was truth for every computer, but i use this functionality in every "LAPTOP" computer that i have access and works. The computers do you test are all "DESKTOPS" computers? if that is the case then this functionality is present only in notebooks computers
    – mjsr
    May 2, 2011 at 15:25

A small Windows program which can be used via command line or GUI is ControlMyMonitor from Nirsoft. It sends DDC commands to the monitor and can (depending on the monitor) change brightness, turn off/on, change the input source etc. To trigger commands, I use it in combination with EventGhost which can react to various event sources (including built-in schedulers, but I have no experience with that).

(I use this combination on multiple computers with a KVM switch to make the monitor change the input source when a computer detects the connection of an input device.)


The only solution that really works for me is ClickMonitorDDC.

It's possible to specify contrast, brightness, and saturation separately, by hour:

b50 means brightness 50, c50 means contrast 50

b50 means a brightness of 50%, c50 means a contrast of 50%

The download from the initial link is not working, but if you google for it, you'll be able to find it easily.

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