How To Save Hard Drive Space On Your Mac

Now that the iconic plastic MacBook series has come to an end, many Mac owners will be considering purchasing a MacBook Air as their primary computer. The Air is an awesome choice and will provide a user experience and build quality second to none, but those blistering SSD speeds do come with some compromise in hard drive space. The article below will guide through some steps you can take and applications you can use, to get the most out of the space you have.

Keep in mind that you don’t need a MacBook Air, or even an SSD to benefit from the tips below, as it can never hurt to de-clutter your hard drive and keep your Mac in good shape, whichever model it is.

Backup First

The following tips are not too advanced or risky and are unlikely to cause any harm to your Mac, but it’s still essential to backup your data fully before moving forward.

If you’d like to make a complete, bootable copy of your hard drive, head over to our guide on doing so using Carbon Copy Cloner. With this out of the way, let’s get started!


AppTrap uninstall prompt

AppTrap uninstall prompt

Apple decided not to include an uninstaller with OS X and most users regularly drag-and-drop unwanted apps into their Trash. There’s nothing wrong with this method (it won’t hurt your Mac), but most of the time there will be plenty of residue of data left behind by the deleted app. This usually takes the form of small preference files, but can sometimes include larger system files too, which can eventually build up over time.

There’s a few different applications which will take care of uninstalling for you and after trying out most of them, I like AppTrap the most. AppTrap is a free program which has a very small memory footprint and unobtrusively runs in the background without you ever having to worry about it. It works like this; each time you go to delete an app, AppTrap will pop up with the above window and prompt you to decide whether to remove this app fully – which means move all associated system files into the Trash, or not. The prompt will also often come on when an app updates itself, so in these circumstances you can just click “no.”

An added bonus of AppTrap is that when choosing a complete uninstall of an application, you’ll know that should you decide to re-install it at a later date, you’ll have a clean slate, as the app won’t remember your preferences.


A typical CleanMyMac scan

A typical CleanMyMac scan

Over time, OS X will store cache files to help it launch and run applications and services more quickly. This is a completely normal and healthy aspect of Mac computing, but over time these cache’s can grow to a significant size and, rather than speed things up, can bloat your system.

The worst offenders are typically web browsers, especially Safari, but other apps can build up cache files too. Cleaning your Mac’s cache is not something you need to do every week, or even every month, but infrequently. To perform this, I love CleanMyMac, an app with many strengths besides just cache cleaning.

CleanMyMac is a flexible and accessible application which can be a one-stop solution to all the space saving tasks covered here, with options for uninstalling applications, cache cleaning and more. Many applications come with code built-in to enable their use on older non-Intel Macs such as the iBook G4 and this code can build up to take away a big portion of hard drive space. Similarly, additional language translations are often buried into an app and this can take up a surprisingly large amount of space too.

A word of caution however: There are some programs which do not perform well after being ‘slimmed down’ in the way which CleanMyMac performs, and in order to protect against this, CleanMyMac comes with its own blacklist. I have never ran into any problems using the application on several Macs, running Leopard, Snow Leopard and Lion respectively – though as always, make sure you’ve got a backup before proceeding to slim your Mac.


Cleaning pane offers choice of cache-removal

Cleaning pane offers choice of cache-removal

Though more of an all-round maintenance tool than confined to space saving alone, Onyx offers enough features and options related to reducing clutter that I feel it warrants inclusion here. On launch, Onyx will scan your system disk for any errors. Following this, the user can then verify and/or repair permissions, delete cache’s and find out system information. As you can see in the screenshot above, choosing the ‘Cleaning’ pane from Onyx’s main window brings up further options to purge the cache, organised by type. Head over to this in-depth review by Quintin to get a closer look at this great free software.

Replace iTunes With Spotify

Spotify has an excellent library of both mainstream and obscure artists

Spotify has an excellent library of both mainstream and obscure artists

Recently reviewed in full here on Mac.AppStorm, Spotify is a great music streaming service which will help save space on your Mac and give you the chance to check out new music too! Music, even when compressed into MP3, is by nature quite large and even the most modest iTunes library can take up a very big chunk of your hard drive’s real estate. By signing up for Spotify, one can have a huge repository of music, anytime and anywhere, so long as you’ve got a healthy internet connection. There are other such services of course (also check out Rdio), but at the moment Spotify seems to be leading the pack and doing so at just $5 a month or free with built-in advertising.

Though it may not be quite practical to completely replace iTunes with Spotify, even just maintaining a bare iTunes library for when you have no internet connection will save you a lot of space!

Move Your iTunes Library To An External HDD

Moving your iTunes Library

Moving your iTunes Library

Should you wish to keep a large iTunes library, you may prefer to move your media to an external hard drive instead. Here’s how to do this:

First quit iTunes and navigate to your iTunes folder on your Mac. This should be in User Name > Music > iTunes – then simply drag and drop the iTunes folder into your external hard drive and wait for it to copy.

Next up, you need to launch iTunes and go to “Preferences” and “Advanced”, then click on the “Change” button to choose the new library location.

Remember to make sure you have another backup before you delete your media off your Mac!

Final Thoughts

Saving space on your Mac has more to do with attitude and approach than any other factor. By running apps like CleanMyMac infrequently and only installing apps which you need to use regularly, you can help save a lot of data and keep your Mac bloat-free. In addition to this and the apps mentioned above, another method of saving space on your Mac is to look for lightweight alternatives to larger programs, replacing Pages with TextEdit, Photoshop with Pixelmator and so on.

Have you got any space saving techniques, tricks or tips? Let us know about them in the comments!


Add Yours
  • You forgot Monolingual ( which wipes all unnecessary language files. I made 8GB of free space with it! ; )

    • I would have included Monolingual but I used it once and right afterwards had a kernel panic, necessitating a re-install of my OS.

      My experience was probably very rare and could have been the fault of something else, but given that it appeared to break my installation, it seemed best not to recommend it – especially since Clean My Mac also removes unnecessary language files.

  • why not just buy a 1TB HD? they are dirt cheap.
    I’ve just upgraded to the 1TB samsung, it’s nice an quite, it’ll take me ages to fill that space up.

    • I guess because most people are moving over to SSD’s now. And given the expensive price it’s best to find ways to save as much space as possible.
      Putting iTunes’ library on an external drive is a real good tip saved me about 10 gigs. Same could be said for iPhoto’s library. Depending on how much picks you have you can use 2 libraries on small one on your machine, and a larger one on an external.

  • *quiet

  • An incredibly useful tool I use is Omni Disk Sweeper.
    It scans your hard drive and puts the folders using the most space at the top of the list, so it’s really easy to spot what’s taking up the most space. You can either move them to an external disk then delete the offending files or just delete them from within the app.
    The best part is that it’s free.

    • Omni Disk Sweeper does indeed look very useful, thanks for the tip!

    • Hello Paul,
      is this Omni Disk Sweeper. works with SSD?

  • The biggest hog on my Mac Book Air is photos. IPHOTO has no space management tools. Argh! And, it’s a pain to backup, export, and delete. For the “throw away” photos, who cares. Some are priceless and irreplaceable. Fear of a mistake freezes one into inaction. Argh! Help?

    • If you like the basic method of iPhoto but need more control, then perhaps Aperture will suit you better.

      I’m not an expert on the application but like it a lot and Aperture 3 offers more control over file management, backup and export and in addition it is simple to import your iPhoto library into it.

      there’s a 30-day trial here;

    • Backing up iPhoto is just a matter of backing up the iPhoto Library file in the Pictures folder. As far as exporting goes, just selecting the photos you want to export and drag them to a folder.

      Another way of “exporting” your photos; you can “Show Package Contents” on that iPhoto Library file (Right-click the file) and get access to the photos stored in iPhoto directly. The “Masters” folder is where all your photos are stored. They are organized by Year and Date.

      Throwing photos into the trash is just like throwing files into the Dock Trashcan. They are not permanently deleted until you “Empty the Trash”.

      Depending on how many photos you have, backing them up to a service like Dropbox or even Amazon’s Cloud service might be an option. If you buy an album from Amazon, you get 20GB’s of cloud storage for a year. Otherwise you get 5GB’s of free storage. 20GB cost $20 a year unless you had bought that album. Then they charge the difference for the first year. I suspect that if you buy an album a year, you wind up paying the difference each year.

      I personally purchased the 20GB option because they offered to store an “unlimited” amount of music for that $20 a year price. I now have 150+GB’s of music stored in their service for that $20 a year price!

  • Mind you, your suggestion of Spotify is clearly not for everyone, but it’s definitely not for me! My iTunes is controlling 1.3TB’s of media, 153GB’s of which is audio. Deleting that audio is just not in the cards for me.

    To be fair, I do have all those songs stored in Amazon’s Cloud player. However, its never safe to assume a cloud service to will be around forever or keep your data safe. They are just as susceptible to HDD crashes as we are.

    Also, I have tried Spotify, and unless I something configured wrong with my iPhone, even paying the $9.95 monthly subscription, I wasn’t able to play hardly any of the songs I currently own on my computer. The free version of Spotify won’t even let you play the songs that they highlight on the iPhone app! To say the least, I am not impressed with Spotify. and are much better alternatives to Spotify. They seem to have better collections of music even though Spotify claims that they have more tracks than Mog or Rdio.

  • Sometimes I am shocked by the oversights in these articles. What about deleting… ahem… your massive hoard of downloaded… jpgs and movs? ;)

    ANYWAY… Xslimmer can be quite useful too, pulling out the unnecessary parts of programs. Also Clusters if you have Lion. It will compress files in the background, though it is quite processor intensive so I turn it off a lot. Even so, it cleared up 9 GB for me so far. I just set it running when I’m not using my Mac.

    • Clusters works with Snow Leopard too. . . I’ve had it installed ever since it was released.

      It’s good to compress files that don’t change too often, like your applications folder, or your music files. Wouldn’t use it for every file on my system though.

  • another thing to note about Spotify (and I enjoy it quite a bit), is that it keeps a large cache on your computer. Not as large as your iTunes library, depending on size, but fairly sizable depending on what you listen too and how many playlists you have.

  • Great tips here, I appreciate it. I especially like the Omni Disk Sweeper, Thanks Paul!

  • I don’t know if it’s possible to use spotify as your default all music player if you’ve offloaded to an EHD to play through iTunes. If anyone knows, please tell me how.
    But, the question I have is about running iTunes through the aforementioned ehd. Every once in a while I open iTunes and it seems to have “forgotten” where to look. It won’t play anything from e time capsule library because it no longer has that information.
    Does anyone else have this problem and/or know how to fix it?

  • I have found that Clean My Mac and Onyx working in tandem work very well.

    Also I’ve found that Spotify is just as bad, if not worse than iTunes in the disk hog department, even after only 10-15mins of playing.

  • I don’t know if it’s possible to use spotify as your default all music player if you’ve offloaded to an EHD to play through iTunes. If anyone knows, please tell me how.
    But, the question I have is about running iTunes through the aforementioned ehd. Every once in a while I open iTunes and it seems to have “forgotten” where to look. It won’t play anything from e time capsule library because it no longer has that information.
    Does anyone else have this problem and/or know how to fix it?

  • This article is very useful. I have used my Mac for years and did not notice my disk is consuming by the useless files. This article helped me much. I also found another free cleanup software CleanGenius Free. It is free and effective.

  • I moved my iTunes Library to my external hardrive and I went on iTunes preferences and updated the new location of the library, now my question is: Do I need to now delete the itunes library that is still in my Mac or its gone after I did the move? please let me know

  • how to do it