How to Disable the Mac Boot Chime Completely
If you’re a Mac owner you know that every time the Mac reboots or starts up it makes a startup chime sound. Though you can temporarily mute the chime by holding down the Mute key on any Mac keyboard, you can also choose to disable it completely by turning to the command line.
Launch Terminal, found in /Applications/Utilities/, then enter the following command to disable the boot chime:
sudo nvram SystemAudioVolume=%80
Enter the admin password when requested, which is required by usage of the sudo command. On your next reboot the Mac will be completely silent. Adjusting the parameter at the end of that command lets you change the total volume of that boot chime, but it appears to favor ascii characters.
To return to the default setting, you can remove the variable with the -d flag.
sudo nvram -d SystemAudioVolume
If you’re not comfortable with making tweaks to OS X with the Terminal, you’ll be better off using the one-off Mute key approach or using a simple tool like StartUp Ninja to silence the sound. StartupNinja is basically just a GUI frontend to the nvram tool discussed here.
Thanks to AnserMan for the tip left in our comments, though they suggested using %00 rather than %80 as the parameter
You only need to press the mute button on the keyboard before shutting down/restarting the Mac and you will not have the boot chime.
yeah… no. That doesn’t work for my Mac.
hmmm….. following your instructions it says, “On your next reboot the Mac will be completely silent.” But then it says I need to adjust the parameter from %80??? So I need to in fact make it %0???
I’m not so sure I understand, “You’ll find a variety of %80.” either? I’ll find a variety? Sorry, I don’t mean to sound facetious….. it’s just frustration because I tried this 3 times before I finally spotted the wording….. I’ll try %0 and hope it works…..
Whoops, a draft of the original article was published rather than the original. My bad!
nope! %0 still produces a log in sound…… this hasn’t worked at all….
Terminal command not work on 10.8.2
To mute the startup chime I use login & logout hooks. Works perfectly. Might be a bit complicated to set up at first for those not familiar with hooks & terminal, but even I managed
1. Login as administrator and open a terminal window
2. Create scriptfile for muting
sudo nano /path/to/mute-on.sh
3. Enter this as content, when done press control+O to save and control+X to exit:
#!/bin/bash
osascript -e ‘set volume with output muted’
4. Create scriptfile for unmuting
sudo nano /path/to/mute-off.sh
5. Enter this as content, when done press control+O to save and control+X to exit:
#!/bin/bash
osascript -e ‘set volume without output muted’
6. Make both files executable:
sudo chmod u+x /path/to/mute-on.sh
sudo chmod u+x /path/to/mute-off.sh
7. Check if any hooks already exist (these will be overwritten, so make sure it is OK for you)
sudo defaults read com.apple.loginwindow LoginHook
sudo defaults read com.apple.loginwindow LogoutHook
8. Add hooks for muting
sudo defaults write com.apple.loginwindow LogoutHook /path/to/mute-on.sh
sudo defaults write com.apple.loginwindow LoginHook /path/to/mute-off.sh
Notes:
- /path/to/ is the location of the scripts, I used /Library/Scripts/
- you can skip the unmuting loginhook (i.e. each logout will silence your machine), but I like it this way because I always have sound available exactly at the volume level I set last time
- root has to be the owner of the script files – running an editor from command line with sudo is the easiest way to achieve that (otherwise you need to chown)
- to delete the hooks, use the following:
sudo defaults delete com.apple.loginwindow LoginHook
sudo defaults delete com.apple.loginwindow LogoutHook
Gee, thanks!
So in order to do a very simple thing one needs an advanced degree in computer science…
I thought Macs were easy to use…
On my MBP all I have to do it turn down the volume of the built-in speakers while in MacOS X, which is different from the volume of the headphone jack that I use all the time.
To do that just unplug the headphones, or any other external audio devices, check that the built-in speakers are selected as the device for sound output in System Preferences/Sound, and adjust the volume. Then select back the sound output device you were using or plug in your headphones.
As someone with an advanced degree in computer science I must have missed the day when we covered basic shell scripting. Oh that right shell scripting is not computer science… that must be why it was not covered.
Um… why the hell would you expect someone who hasn’t done coursework in computer science to know what’s covered in a computer science degree?
Given that you have an “advanced degree in computer science,” why are you trolling the Web for a pointer on how to silence the Mac start-up chime? Then again, props to you for chiming in with an unrelated post about your academic achievements. I imagine your classmates from the “University” of Phoenix will be impressed to seeing you weigh in on the critical computer science issues of our times.
Brilliant. Advanced computer science degree? WTF
Not a good idea. The boot chime actually means something when doing diagnostics. I encourage you to just mute your sound if you don’t want to hear it… Otherwise if you take it in you will end up with a completely rebuilt system and your problem not solved.
LOL! Mac users are so cute.
looks like you are not familiar to mac if saying that.
boot chime is not just a “fancy startup sound”, you should know that its a first diagnostic tool for your mac, notifying you if something wrong from the startup..
so tryin to disable it will be a big mistake. just 2cnts for you
Again LOL. All the information needed is output via the diagnostic port. Have you never seen the “geniuses” scan a computer for problems. The dong is just branding. A diagnostic tool that is rendered useless by muting the sound before rebooting would be pretty stupid.
Like I said Mac users are so cute.
If you hear the chime (the actual name for it), it means the system passed all the POST (self-test) checks so it’s useful in that regard. If it isn’t heard, isn’t muted, and the logic board/CPU/speaker isn’t completely dead you will hopefully hear a series of beeps, the timing and number of which indicate the component that hasn’t passed POST checks (often bad RAM).
The nvram value that causes muting isn’t universally the same.
An iMac11,3 (not sure of the year) and 2012 15-inch MBP Retina, each with a factory default chime volume, have the SystemAudioVolume attribute set but the value is null/empty.
A 2010 Mac Pro has the attribute set to ’0′ (not %00) after previously muting it and then doing a PRAM reset to get it back to default.
A MacMini5,2 and MacMini5,3 have the attribute with a value of ‘V’.
A MacBookPro2,1 (early 2007) has the attribute with a value of ‘i’.
Aren’t we?
Totally helpless sheeple
Hi, is it possible to replace this sound by another ?
edit : or to extract this sound in order to get an mp3 / wave / whatever file ?
The sound is encoded into the system EFI (BIOS) and cannot be changed.
It is also trade-marked. The only other “device” licensed to use it is Wall-E
Wally had a pretty crappy boot system anyway…
on my doddery old 2008 Mac Pro, it took:
sudo nvram SystemAudioVolume=’ ‘
which was a hint I saw elsewhere.
The name of the tool is StartNinja.
I’ve got the a previous gen MacBook Pro, but this hint doesn’t work, nor does Startup Ninja. Perhaps it’s because the headphone was plugged in?
This is one of the stupidest Apple things I’ve come across. I have a MBP running 10.8. I cannot mute or change the startup sound level from what it was set to last. I don’t know why the “hold mute key” option is gone. Next thing Apple is going to take away the power button because, of course, we Apple zombies never want to turn off our devices!
Wow, this thread went down a rabbit hole, huh.
I did a quick
man nvram
saw an option to print current values
nvram -p
ran that and noticed “off” settings seemed to be=%01 so ran
sudo nvram SystemAudioVolume=%01
and that worked for me running 10.8.2
Thank you for getting to the point. This commentary is almost as annoying as how complicated it is to do something that should be very easy. I thought Macs were user friendly.
i hate that startup chime!
and to all the idiots saying it is necessary in case something goes wrong…
HOW ABOUT HAVING A CHIME WHEN SOMETHING IS ACTUALLY WRONG – AND NOT THE OTHER WAY AROUND!
absolutely idiotic…
love my mac though… but some things are fking irritating like the stupid startup chime…
sorry jchlu that doesn’t seem to do anything…
Try %d1
as in sudo nvram SystemAudioVolume=%d1
Works perfectly for my MacBookPro OSX 10.8.2 …
Thanks
This sudo command works changing the numbers “00″
“sudo nvram SystemAudioVolume=%80”
Get an app from the App Store called “Calm” it cost me £2.49 but it works a charm on my iMac running 10.8.3.
There’s also a Calm Lite for £1.49 which does a similar thing.
@jchlu
You’re the most sane person here. Thank you.
Don’t stop the car for lurching trollers, hit them.
“sudo nvram SystemAudioVolume=%05”
and
nvram -p
to double check it worked perfect on 10.8.2
what a wonderful system Mac is. it takes a 100 experts to turn off a bloody annoying sound. moron jobs
“sudo nvram SystemAudioVolume=%20″
works for me, late imac 2012, OS X 10.8.3.
%20 means its just 20% loud so you can adjust it as you want. Weird thing is that after using this command my mac is restarting and booting slower than befor :/ And its just 3days old imac so
(