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!