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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.
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On which operating system would that be? It doesn't do anything for me here on Windows 7. – oKtosiTe Dec 8 '10 at 20:29
Linux. Windows probably uses <Super><Shift><L> or something pretentious like that. – Ignacio Vazquez-Abrams Dec 8 '10 at 20:59
What we really need is something that does this for all those blindingly-bright electronic billboards. – Martha Dec 9 '10 at 0:32
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 '10 at 0:39

16 Answers 16

up vote 11 down vote accepted

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

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Sadly, this did not work for me--said my monitor is unsupported. :( – Sasha Chedygov Dec 15 '10 at 10:22
@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 '10 at 12:06
Sweet, Gamma Panel works. Thanks for the link! – Sasha Chedygov Dec 15 '10 at 22:22
The software has been retired from that website – Filippo Mazza Jun 12 '13 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
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Sometimes monitor/laptop's adjust buttons ain't enough.

For Linux:

xcalib -invert -alter # will invert the color under Xorg, 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.

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f.lux will adjust brightness through out the day to ease eye strain.

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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 '10 at 11:33
(@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 '10 at 22:38

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.

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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 '10 at 23:26

The hormone melatonin is produced by the pineal gland. Higher levels of melatonin normally occur at night. It's effects include causing drowsiness and lowering body temperature. Exposure of your eyes to bright light suppresses the production of melatonin so when you crawl into bed in the wee hours you'll be lying awake wondering why you can't sleep.

Fastest, most effective way I know to reduce screen brightness is to reach for the power switch. This has the added benefit of not screwing with your circadian cycle by causing artificial levels of melatonin.

Slightly less annoying answer: Reach for the Ray-Bans, no seriously, this works for me.

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

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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.

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

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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.
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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.

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Care to elaborate at all? – random May 2 '11 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

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But does it work on regular PCs? – oKtosiTe Jul 18 '12 at 7:42

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).
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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.

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Bring up windows mobility center (Windows key shortcut: Win + X), many options including screen brightness. i use this all the time.


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This has already been suggested, and doesn't work on presumably most desktop computers. – oKtosiTe May 9 '12 at 7:32

I found ClickMonitorDDC from a recommendation on Superuser:

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

Just to control brightness and contrast I'm using (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.

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