A full startup disk is something that every Mac user will experience. This problem used to be known as “Startup disk full” notification. However, on newer macOS versions this message has been changed to “Your disk is almost full.”
But luckily, it’s a problem that has many solutions. And in this article, we’ll go over:
However, we also understand that some people are short on time and just want to fix startup disk full. So, if you’re not really interested in what it is and why it happens, just skip the next two sections and head to “How to Clean Your Startup Disk”.
Apple has included the ‘disk is almost full’ warning for a reason, as Mac OS does require free disk space to operate. In fact, you are better off keeping at least 15% of the disk capacity available at all times if you don’t want to start experiencing occasional hick-ups and errors. How to free up space on a Mac? What is a “Mac Startup Disk”? Your Mac startup disk is a volume or a partition of a drive that contains a usable operating system. You can set your Mac to automatically use a specific startup volume, or you can temporarily override this choice at startup.
Or, even better, if you’re looking how to clear space on Mac, we’d highly recommend a utility called CleanMyMac X. It'll help you clean up gigabytes of disk space in just minutes (you can download it here).
Note: if you’re running a newer version of macOS, it has a built-in option of Optimized Storage that is supposed to solve the problem of the full hard drive by moving files into the cloud.
By clicking 'Manage' you can open the menu and see what Optimized storage offers. However, it moves junk and useless files to the cloud together with your files, and eventually, you end up paying for iCloud storage to store junk. So we still recommend getting CleanMyMac and actually dealing with extra files rather than simply moving them.
Now, with all that said, let’s get into what exactly “Your disk is almost full” means.
The Mac drive with the OS on it is the startup disk while the other drive is just used for storage of files. It’s possible to have multiple startup disks, but most Macs will only have one. And for proper disk cleanup on Mac, all drives are just as important. Startup Disk Full Fixer is the best Mac cleaner, which allows you to find and remove all junk files and save disk space by removing them. Launch the application to preview:. Startup disk volume capacity. Space already used on your startup disk. Free space left on the startup disk. FIXING “STARTUP DISK FULL” ERROR. What’s a startup disk? A startup disk is a partition of a drive or a volume that contains a usable operating system. Your startup disk doesn’t have to contain macOS. For example, your Mac can boot directly into Windows if you’re using Boot Camp. It can also boot into Ubuntu or any other operating system supported by your Mac’s hardware.
A startup disk, as taken from Apple Support article, is a volume or partition of a drive that contains a usable operating system. Still confused? Let’s break it down for you.
Your Mac hard drive consists of disks (or partitions). Each disk (or partition) has your Mac data on it, which consists of your operating system, applications, etc. Most Mac users have just one disk but power users may have two or more.
Let’s look at an example of a Mac with only one hard disk:
A Mac with two disks will have the storage divided between them. The Mac drive with the OS on it is the startup disk while the other drive is just used for storage of files. It’s possible to have multiple startup disks, but most Macs will only have one. And for proper disk cleanup on Mac, all drives are just as important.
This is easy. It’s a lot like why is your fridge full? There is no more space! Your disk is almost full and this is very bad news for any drive. A hard disk should never get beyond 85% capacity (especially a startup disk) as you will experience slowness and errors the further you get above that mark.
If your startup disk is full and you get a message of warning from your Mac, this is a serious indication that you need to clear up storage immediately.
So how do you fix your almost full startup disk? The same way you solve the problem of a packed fridge - you need to clear up storage, of course. To make more space on your startup disk you will need to:
So, now that we know what a startup disk is, we need to talk about how to fix it. Let’s take a closer look at your disk space to see exactly what is causing your disk to be almost full.
Short version: Take a look under-the-hood of your Mac.
Before we can see what is taking up space on your startup disk, first we have to find it:
After selecting this box, your desktop should now show the hard disks on your Mac, in the form of icon(s), like this:
These are disks on your Mac that you can “startup”, this is because they have operating systems on them. If there is more than one of these hard disk icons that show up on your desktop, it means you’ve got multiple hard disks on your Mac. If you only have one, skip the down to “What is taking up all of my startup disk space?” section.
If you have more than one, continue with the next step:
Click on the Apple icon at the top left of your screen System Preferences > Startup Disk.
Here, again, you’ll find your hard disk(s); they’re probably named something like MainSSD or MainHD. It will also display “OS” and the version number of that OS. If you have more than one OS drive, your startup disk should be the one with the latest version of macOS running on it, but we’re going to make sure of that in the next step.
I only have one and it looks like this:
To make 100% sure that you know what drive is your startup disk, follow these steps:
See how my version number in the “About This Mac” window matches the number in my Startup Disk section? Yep — That’s my startup disk. Found yours? Good.
Now that we’ve identified our startup disk, let’s take a closer look at how to clear up space on Mac:
Take a look at my hard drive disk:
I’ve got 500GB of storage, and about 275GB of it is free.
So, how big is your hard disk? How much free space do you have (if any — *gulp*)? And what’s taking up the most space? It is important to consider drive capacity and data storage needs for future storage plans — we’re not just here to fix the problem, for now, we’re going to make sure you never have this problem in the future as well.
Now that we have the knowledge, it’s time to take action and fix your Mac’s “Startup Disk Full” problem.
Let’s go over 11 things you can do to help fix 'your disk is almost full.' These should also give you other ideas as to how else to fix it — You know your Mac better than we do!
System storage cleanup sounds like a serious undertaking. But, technically, it boils down to just one thing: having the courage to scrap the old files.
This app gives you lots of possibilities to free up space, especially when it comes to system junk. CleanMyMac X has been notarized by Apple, which basically means it's safe to use. And if you got 5 minutes, try this tool as it shows you where exactly your junk hides.
Cache files are files that help your Mac run programs a bit more smoothly. Think of them like blueprints for a house: your Mac has the blueprints for how a program is supposed to load/run/look, so it loads it faster; without them, it’d be like building it from scratch. However, over time, these caches can start to take up some serious space. Periodically, removing them can help clear storage. And don’t worry, your Mac will create fresh, new ones after you restart your Mac. To remove caches:
Deleting cache files is generally safe for your Mac. And once you delete them, the applications and processes you run on your Mac will generate fresh, new ones. But, when deleting, worry more about removing them based on size rather than just removing all of them.
Also, you can check the /System/Library/Caches folder as well, but it might be better not to touch this folder without knowing what the items are. A utility that correctly cleans up these files (and pretty much everything else on this list) is, you guessed it, CleanMyMac X. It cleans up even your system caches with just a few clicks.
Oh, and once you’re done with this list, restart your Mac so it can create these new cache files.
Read more: How to Clear Cache on a Mac?
Localization files are also known as “language packs.” Lots of apps come with other languages that you probably don’t need. To clear up space on your Mac, delete the ones you don’t need:
From here, go to Contents > Resources and look for files ending in .lproj. These are the languages your app has just in case you want to use it in another language, like Spanish (es.lproj). Drag the ones you’ll never use to the Trash.
Again, a safer alternative to this would be to use CleanMyMac X. It gets rid of all of them with a click. No digging through application folders, just a cleaner Mac.
Read more: How to Delete Language Files from macOS?
Even if you have the most organized Mac on a planet, duplicates happen one way or another. It can be a file you’ve mistakenly downloaded twice or a mail attachment you’ve opened several times. Regardless of how they appeared, those files sit on your Mac and gobble up storage.
But finding and deleting them is a time-consuming process if you do it one by one. So here’s what you can do for a simple Mac disk cleanup:
Remember to pay attention to the date of creation to make sure you keep the true original, not the copy.
While this is the best way to remove duplicates manually, it takes lots of your time and dedication. It’d be much easier to leave this to Gemini 2: The Duplicate Finder.
This app quickly scans your Mac for duplicate and similar files and allows you to delete them within minutes. It keeps your originals safe and helps you easily retrieve files deleted by accident.
Backups can tend to take up a lot of space. You can find and remove them by:
Get rid of all the old, outdated backups your Mac has been storing for a bit more extra space.
Keeping many large files on your Desktop and in Documents slows down the system. And if you delete only a couple of these enormously large files, you can get half of your storage back.
Let’s open the familiar About this Mac pane once again. If you click Manage, you’ll see this window for sorting files.
While this instrument is good for finding large files, it misses a lot of things. See that “Other” category that takes up 38.GB?
To deepen your search for massive files, use this tool from CleanMyMac X. It’s called Large & Old files finder.
It’s much more helpful as it shows you lots of other categories of files, like Archives. The app breaks your files by Size and Last Used.
To see this instrument in action, download the free edition of CleanMyMac X. And click the Large & Old files at the bottom of the sidebar.
This isn’t often overlooked, but definitely under-appreciated. Removing old, unused applications is a great way to get some extra space on your startup disk. Go through your applications folder and get rid of all the apps you rarely use. But make sure you remove them correctly, don’t just drag them to the Trash. If you do, you’ll leave behind tons of leftover parts and pieces, and we’re trying to get back startup disk space — It’ll kinda defeat the purpose, no?
This is another place we’d suggest using CleanMyMac X. To completely remove any application, just launch CleanMyMac X, click Uninstaller, select your application, and then click Uninstall. You won’t have to search all over for development junk that’s left behind when Trash’ing an application. It’s incredibly easy and saves you tons of time.
When your local storage is full to the brim, your Mac will start uploading this data to iCloud. But only if you have this setting enabled. Is your Photos app synced with iCloud already? Let’s check.
Ticking the box iCloud Photos will connect your Photos library to iCloud. And what’s more important, if you select Optimise Storage, some part of your Photo library will be moved to iCloud. This way you macOS saves precious space. The free iCloud plan allows you to free up at least 5 GB worth of storage.
The similar logic applies to your Documents and other files. To set up the cloud backup with iCloud drive, go to System Preferences > Apple ID > iCloud.
Have a closer look at these three folders. You’d be surprised at how many downloads can accumulate when you aren’t paying attention. Clean out anything you don’t need (or don’t know) and organize the rest. It’ll take a load off your mind to know that there’s nothing excess there.
The Movies folder can be a pain, not because you’re searching through tons of files, but it can be difficult to choose what to delete. Personally, I never want to get rid of Top Gun. It’s amazing. I watched it 3 times in a row last weekend. But alas, sometimes you need to make sacrifices for the health of your Mac. Though, what you can do with movies you want to keep is to archive them. So, archive what you wish to keep and remove the rest.
Archiving a file doesn’t mean to store deeper into the abyss of your Mac — but to turn the file into something smaller, into a compressed file (like .zip or .tar). By archiving a file, you shave off some memory. Archiving is essential for things you want to keep on your Mac, but don’t often use, and helps you clear up some space. And that’s what this is all about right? We’re essentially doing the hokey-pokey on your Mac. To archive a file, just:
The last place to sweep through is the Music folder. Find and remove duplicate music files first, and then clean up all the songs you downloaded on a weird Sunday afternoon cleaning the house.
“Clean my desktop… but why?” Because some people’s desktops are hard to look at, that’s why. Organize your desktop and get rid of the stuff you just don’t need on there. It looks better and helps your Mac act a bit faster (I don’t know the rocket science behind this one, but it feels too good to be false). Your Mac doesn’t waste time loading all those icons and junk, just… Just clean it, please.
Seriously: It may sound incredibly basic, but it could clear a surprising amount of storage. I forget to do it all the time. The thing is, that when you delete something, your Mac doesn’t remove it — it just moves it to the Trash. Plus, you’ve probably deleted way more than you realize, and all that could be sitting in the Trash, wasting space. So get rid of all that junk by emptying the Trash:
And, the easiest step is done.
1. Manage your Optimized Storage
This option comes with your operating system starting macOS Sierra. Go to the Apple menu > About this Mac > Storage
Now, click on Manage to reveal the space-saving options:
2. Erase your Junk Mail
Open your Mail app, and click Mailbox in the upper menu. Here you can erase spam and already deleted items.
We’ve cleaned up a few things on your Mac, and hopefully, it’s given you more ideas as to what else you can clean. But, let’s take a look at how much space you saved from cleaning the list above. Remember how we checked your Mac’s free space? Open that window again and see how much space you’ve cleared up:
You’ve probably got a bit more space, and you’ll want to keep it that way. The only way to prevent a “your disk is almost full” is by keeping your Mac clean. We’d recommend a complete cleaning every 2–3 weeks.
We've told you how to delete storage on Mac in multiple ways. Hopefully, this has helped you fix that full startup disk problem. Your startup disk should now be quite a bit lighter (we hope). Oh, and if you liked this article, get social with it to help others in need. And if you really liked this article, subscribe to our email list — we’ve got more guides on the way. And we’ve also got a utility that’ll help you out a ton in the long run: CleanMyMac X. It helps you clean your entire Mac with just the click of a button. It’s incredibly easy to use and works like a charm.
/Browser Cleanup /Startup Disk Full on Mac? 11 Tips to Free up Space!
As I was using my MacBook Pro today, a message on the screen appeared. It said that the startup disk is almost full. Is there something wrong with my Mac? What can I do to get rid of startup disk full Mac?
There is no need to panic! Just follow our tips on how to clean up your full startup disk on Mac and you should be back on track. I have just the perfect solution for you.
Article GuidePart 1. What is A Startup Disk?Part 2. Why Is My Startup Disk Full?Part 3. How Do I Delete Files on My Mac When the Disk is Full?Part 4. Conclusion
What is the startup disk on a Mac? A startup disk is actually a partition of a drive which contains a valuable operating system. This means that the hard drive of your Mac does consist of disks. Each of these disks contains the data on your Mac. These data are your operating system, applications, files, and more. Most of Mac’s products actually have just one disk, however, power users have the capability of having two or more.
A Mac that only has one hard disk has the following features:
However, if you actually have a Mac that has two hard disks, then that means that the storage indicated above will be divided into two. One of them will have your operating system and the other one will serve as your storage for your files. Still, startup disk full is an urgent thing to deal with. Let's learn why is your startup disk full (Mac) and how to free up the space to get a new Mac.
At one point or another, a Mac user will see “Your startup disk is almost full” on their screen. While this is a problem that requires prompt action, it isn’t the end of the world. You get this error because your primary disk drive is running out of space, which makes your Mac run slowly. The startup disk is the hard drive where your operating system is stored. That makes it the most essential disk on your Mac. It also contains user data such as apps and files.
Having a startup disk that is close to full poses two problems:
Ideally, 10% should be left free on your startup disk to provide enough space for your Mac to work well. Always remember that a hard disk should not go beyond 85% capacity. If this happens, then your Mac will perform slower and you will have more errors in using your Mac when you go beyond 85%. Startup disk is full how to fix? What to do when startup disk is full? Of course you need to remove files from startup disk.
Of course, the first thing that you should do is finding out what data is actually eating up storage on your Mac. Here is how you can locate your startup disk.
After that, your Mac will then start to show you its hard disk in an icon form. These are actually the disk/s that you can start up. The reason for this is because they carry your Mac’s operating system. If it happens that you have more than one hard disk, then go ahead and follow these steps:
After that, you will be able to see your hard disk again and they might carry names like “MainSSD” or “MainHD”. You will also be able to the operating system that is running on your Mac. If it happens that you have more than one hard disk, then your startup disk is the one that is carrying the latest version of macOS.
Now, here is how you will be able to see what are the things that are actually taking up space and make your startup disk full (Mac):
How to clear disk space on Mac? Cleaning up your Mac’s full startup disk is easier and quicker if you’re using the right tool. An excellent example is iMyMac PowerMyMac, it helps you check and free up more disk space on the startup drive. It removes the unnecessary files that take up your disk space, including system junks, duplicate photos, mail attachments, iTunes old backups, browsers caches, apps, ect. Just with a few clicks, you will have more disk space released and can really fix startup disk full (Mac) issue.
So how to clear my startup disk? Well, you’ll find out just how much junk files you have once you download and use the software to free up space on Mac:
Now you know how to free up disk space on a mac with iMyMac. In order to free more space on Mac startup disk, just go back to the left-hand side of the screen and repeat steps 1 to 3. In this case, you have to select Large & Old Files, Duplicate Finder, Uninstaller or other functions to remove other unnecessary files in your disk.
Did you know that every time you decide to update iTunes, it creates a backup of your iTunes library? This just gives you a whole lot of backups that you don’t even need. That’s why this is a good place to start to clear up your startup disk and fix startup disk full (Mac). After all, you’ll only need one backup. Here’s how to look for your backups and get rid of them:
If you have an iPhone or iPad and you update them using iTunes, you likely have a ton of backups in your Mac. Follow the steps below to get rid of them:
Aside from creating backups of your iDevice’s files, iTunes also downloads updates for your device’s apps. Once your apps are updated, the updates no longer serve any purpose. They simply stay on your Mac and waste space. Here’s how to look for them and remove them:
Cache files help your Mac run applications faster. However, they accumulate over time as programs generate temporary files. They remain on your Mac and eat up disk space if you don’t delete them yourself. When you get rid of cache files, the priority must be with removing the largest files so that startup disk full (Mac) issue will be solved.
Do not delete everything. Moreover, we recommend deleting the files inside the folder instead of deleting the entire folder:
Your apps may come with language packs that allow you to change the language in the app. It’s a great option, but let’s admit it. We only use our app in one language. We can get away without the rest. Here’s how to clean them up:
Look for files ending in .lproj. These are the language packs. Select those that you are not going to use and delete them. Repeat the steps for other apps.
Many users have numerous apps that they have never launched. In such case, there is no better way to free up your full startup disk than to remove old and unused apps.
We suggest using iMyMac PowerMyMac's Uninstaller for fixing startup disk full (Mac) purpose. Dragging an app straight to Trash can leave behind hidden files such as app logs. However, this tool successfully uninstalls the app and deletes associated files along with it.
Every time you visit a new page on your internet browser, it generates cache to make it load faster on your future visits. Doing this on every page, though, will lead to a growing browser junk. How you remove browser cache that may differ for different browsers? Visit the support page of the developer for more details.
Your Downloads folder is a goldmine of unnecessary files. There is also a big chance that you don’t even remember downloading a couple of them. Get rid of everything you don’t need, and try to organize your files. You’ll thank yourself for that in the future. Check out your folders for photos, music, and videos as well. This will be a good way to fix startup disk full (Mac).
There are files that we don’t use that often but we need to keep. The best option for these is to compress and turn them into smaller files. It’s just easy to do that. Ctrl + Click the file that you want to compress and hit Compress. This is recommended for huge files like movies and videos.
After deleting all those junk, they are just sitting in the Trash. Now it’s time to get rid of them – for good. Click on the Empty button, and this should free up considerable space in your startup disk.
Now that we have already discussed everything about your startup disk full (Mac), then it is time for you to remove items from startup disk and to prevent it from getting full. Remember that a full startup disk will cause your Mac to get slow. You should regularly clean up your Mac to ensure that it is performing optimally and you have sufficient space for your files. Don’t worry, iMyMac PowerMyMac will make it a breeze!
This tool is one of the things that you should have for you to be able to keep your Mac safe, clean and of course, healthy. Just have a free trial below.
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Free DownloadBay2019-03-19 19:06:20
Thanks a lot. Usually, I would just empty the Trash, but apparently there's more around. Now I have ideas to clear up some more space.
iMyMac2019-03-20 09:05:24
Thanks for your support!
Pachers2018-10-22 14:05:24
I'm new to Apple and have no idea to my Mac startup disk full problem. Thanks for your tips, I have cleared almost 100gb space and now I can download my favorite movies again!
iMyMac2018-10-22 17:13:07
Thanks for your support!
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