Freeing Up Hard Disk Space
From Mac Guides
To free up hard disk space, the first step is to know what to remove.
Empty your Trash
The most basic thing is to empty your Trash regularly. Unless you're unsure of whether you may need a deleted file later, there's no reason to have a Trash brimming with files.
But this is not the only trash you need to empty. Empty the trash in iPhoto, iMovie, and Mail too.
Remove applications you don't use
Your Mac comes with a lot of commercial applications on a trial basis (like Microsoft Office, FileMaker etc.). If you know that you're not going to use those applications, remove them! Open your Applications folder (with command-shift-A in Finder), drag unused applications to the Trash and then empty the Trash. Trashing the application may only remove its core files. To reclaim more space, manually search and remove application preference and support files, or try to use uninstaller tools like CleanGenius or AppZapper to uninstall applications.
Remove disk images from downloaded files
Whenever you download applications to install, delete the disk image (.dmg) files. See this section in Installing Applications in OS X for more detail.
Clear web browser caches
To improve performance, all web browsers store downloaded pages and files in a cache so that they can re-use those files (instead of re-downloading them) if you visit those same pages again. Clearing the cache could provide some free space. Although clearing the cache for security reasons is a good thing, it reflects very poorly on your disk space management skills if you have to do it to save space! Clearing the browser cache can be done in the your web browser's Preferences window (command-,).
Remove disk space hogs
Delete data that you don't need, or move them to an external hard disk, CDs or DVDs. To avoid wasting time in moving or deleting files or folders that don't provide a huge benefit, first take stock of what you have and find out which folders or files occupy a lot of space. To do this, you could download and install an application, like the free application Disk Inventory X (please consider donating some money to help the developer). Run it and it will show you the space used by various kinds of files in a hierarchical order. Once you know which ones to delete, move them to the Trash (or hit command-delete), then empty it.
Run maintenance utilities
Free system maintenance utilities like MainMenu or Onyx can help clean up temporary files, system caches and logs (please consider donating some money to help the developers). This should also be considered more as a maintenance task than a disk space saving task.
Archive your E-Mail
Saving every copy of every email to the harddrive may not be an option when space is tight. Consider archiving the email.
- Download the application AppZapper and go through your application folder, removing all unneeded and unused applications you can find.
- Remove all system and application localization files not used for your language. Removing these does not remove the ability to read and type languages other than English, just to run your entire system or applications on these languages. Download the application Monolingual or DeLocalizer to make it easier.
- Open iPhoto and delete photos you no longer need. iPhoto has its own application trash so remember to empty afterwards.
- Open iMovie and do the same, including trash.
- Open iTunes and delete all of the music and podcasts you no longer like or need. Remove all the album covers (artwork) in iTunes. Depending on the size of your music library they may use hundreds of megabytes. To delete all artwork at once, select all the music in your library and press Apple-I (Cmd-I). In the Multiple Song Information window find the empty artwork field on the right. Click the checkmark next to it. This deletes all of them. Empty iTunes trash.
- Convert your iTunes music to a compressed format. Many people change the import feature to the lossless AIFF format to burn CDs and then leave the files in that format. To check what format your music files are, CTRL-click the title bar with the song names, time and artists and select Kind from the context menu. If they are AIFF format, change the import format in the Preferences to AAC, then select the AIFF songs and CTRL-click to bring up the context menu and select Convert Selection to AAC. Trash the AIFF files.
- Spend some time and go through your Documents, Movies, and Pictures folder, deleting any junk you no longer have any use for.
- Clear out old email messages in Mail or other email program. Empty their trash too.
- If you have deleted an unneeded user from your system, unless you clicked Delete Immediately, you will have compressed deleted user accounts in your Users folder. If you did an Archive and Install, then you will have a Previous Systems folder. Trash them too.
- Go to ~/Library/Caches/, and delete anything you see from applications you no longer have installed. Repeat the process in ~/Library/Preferences/.
- Go to ~/Library/Safari/, and delete the “Icons” folder. This stores all of the favicons on websites, which appear next to the URL. This can also speed up web browsing speed in Safari.
- If you don’t use it, remove Mac OS 9. To remove it, drag the "System Folder" and the "Application (Mac OS 9)" folders to the trash from the root of your hard drive.
- If you don’t need it, remove the Xcode installer, located in /Applications/Installers/.
- Go to ~/Music/GarageBand/ and delete any GarageBand demo songs.
- Remove unecessary iChat icons from ~/Pictures/iChat Icons/.
- Leave your Mac on overnight from 3 AM - 5 AM. Mac OS creates temporary files that document the system operation. These temp files are cleaned up automatically at night.
- Finally, remember to empty the Apple trash on your dock again.
Once you have done everything on the list, you should have a nice, clean hard-drive, with plenty of free space. If you are still lacking on the free space, you could purchase an external hard-drive. Before you do, run some applications listed below as a final clean up spree to free up more space.
Useful Cleaning Applications
CleanGenius is an all-in-one Mac system clean utility combined with app uninstaller, duplicate finder, big files finder, memory free, login items management, disk space monitor and disk ejector. It cleans potentially unneeded files, removes the unwanted applications and related files.
iDefrag is an advanced Mac OS X disk defragmentation and optimization tool. While there is other software like this on the market, iDefrag is considered to be simpler to use. However, the demo won't defrag a drive more than 100MB in size.
WhatSize is a simple tool that allows the user to quickly measure the size in bytes of a given folder and all subfolders and files within it. The files and folders are automatically sorted by size, with the biggest sizes first.
MacJanitor runs Mac OS X maintenance scripts that don’t otherwise run when your system is asleep or shut down. Running these scripts cleans up System logs and temporary files created as part of the UNIX underpinnings of Mac OS X.
Monolingual a program for removing unnecessary language files from Mac OS X, in order to reclaim several hundred megabytes of disk space.
Delocalizer program removes unneeded language files.
Macaroni is a preference pane that will automatically run the Mac OS X maintenance scripts without user intervention.