How do I delete everything on my Mac computer?

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How do I delete everything on my Mac computer

Completely wiping a Mac computer can be necessary for various reasons. You may want to permanently erase all of your personal data before selling or donating your Mac. Doing a full reset can also help improve performance if your Mac is running slow. Or perhaps you simply want to start fresh with a clean installation of macOS.

Deleting everything on a Mac is a fairly straightforward process, but there are a few different methods you can use. The best approach depends on your specific needs.

Quick Ways to Delete Personal Files

If you just want to delete your personal files like documents, photos, music, and settings, you have a couple quick options:

  • Empty the Trash – Any files you’ve deleted recently are stored in the Trash. You can permanently delete these files by emptying the Trash.
  • Use the Finder – Delete your files manually by navigating to locations like Documents, Downloads, Desktop, etc. and moving files to the Trash.

This will remove your personal data, but won’t make any changes to the core macOS system files.

Reset Your Mac With Erase All Content and Settings

For a more thorough deletion, you can use the “Erase All Content and Settings” option.

This will:

  • Delete all your files and user data
  • Remove all user accounts on the Mac
  • Reset system settings and preferences
  • Reinstall the current version of macOS

Your Mac will essentially be returned to its out-of-the-box state while retaining the current OS version.

To use this option:

  1. Restart your Mac and immediately press and hold Command + R keys to boot into Recovery mode
  2. Select Disk Utility > Continue
  3. Select your hard drive in the sidebar
  4. Click Erase button > Choose APFS format > Name the drive > Erase
  5. Quit Disk Utility
  6. Choose Reinstall macOS from the Utilities window > Continue
  7. Follow the onscreen prompts to reinstall macOS
  8. Select Erase All Content and Settings when prompted

This will completely clear out all previous data and settings and reinstall a clean version of your current macOS. It typically takes around 20-30 minutes to complete.

How to Delete Everything and Revert to Factory Settings

You can fully restore your Mac to its original factory settings using macOS Recovery:

  1. Start up your Mac and immediately press and hold Command + Option + R keys
  2. Select Disk Utility > Continue
  3. Choose your hard drive
  4. Click Erase > Choose APFS format > Name it > Erase
  5. Quit Disk Utility
  6. Go to Utilities > Reinstall macOS
  7. Click Continue to begin install of macOS that came with your Mac
  8. Follow prompts to install
  9. Select Set Up as New Mac when prompted

This will completely wipe your hard drive and reinstall the original macOS version that your Mac came with. It will be like you just unboxed your Mac for the first time.

How to Securely Erase a Hard Drive on Mac

Before selling, trading in, or gifting your Mac, you’ll want to make sure all your personal data is securely erased from the hard drive.

Simply deleting files or reformatting the drive doesn’t remove the data completely – it can still be recovered with the right tools.

To prevent this, you need to securely overwrite the contents of the drive. Here’s how:

  1. Restart Mac and hold Command + R to enter Recovery mode
  2. Go to Disk Utility
  3. Select your hard drive
  4. Click Erase button
  5. Choose Most Secure method from the dropdown menu
  6. Click Erase – this overwrites the drive with random data

Using the Most Secure method performs a 35-pass overwrite and meets Department of Defense standards for securely erasing data.

Alternative Method With Terminal

You can also use the diskutil command in Terminal to securely erase free space on a hard drive. This overwrites any previously deleted files.

  1. Open Terminal
  2. Enter diskutil secureErase freespace LEVEL /Volumes/DRIVE
  3. Replace LEVEL with 1, 3, or 7 pass overwrite
  4. Replace DRIVE with your actual disk name
  5. Press Enter and overwrite will run

Completely Wipe a Mac SSD

Erasing SSDs works a bit differently than traditional hard disk drives. TRIM and wear-leveling can allow data remnants to persist after an erase.

To fully wipe an SSD on Mac:

  1. Boot into Recovery mode
  2. Open Terminal from the Utilities menu
  3. Type diskutil secureErase freespace LEVEL /Volumes/DRIVE
  4. Use a 7-pass overwrite (LEVEL=7)
  5. Reboot and hold Option key to select Recovery HD
  6. Open Disk Utility and format SSD as APFS

This process will completely refresh your SSD by overwriting all cells then reformatting. All data will be erased.

How to Wipe a Mac Without Disk Utilities

If you can’t access Disk Utility or macOS Recovery, you still have options to completely erase your Mac. Here are a couple methods:

Use Target Disk Mode

Target Disk Mode allows you to connect your Mac’s hard drive to another Mac or Windows PC and directly access the drive. You can then use Disk Utility or the PC’s disk tools to wipe the drive.

  1. Connect the two computers with a Thunderbolt or FireWire cable
  2. Boot the Mac to be erased while holding the T key to enter Target Disk Mode
  3. The Mac’s drive will show up as an external disk on the other computer
  4. Use the other computer’s utilities to securely erase the Mac drive

Boot From an External Drive

You can also boot from an external drive or bootable installer then format the internal drive:

  1. Make a bootable installer on an external drive
  2. Boot the Mac from the external drive by holding Option on startup
  3. Open Terminal and enter diskutil list to find internal drive
  4. Use diskutil secureErase to wipe the internal drive
  5. Reformat the internal drive

This will let you bypass the internal drive completely while you erase it.

How to Securely Wipe Free Space on Mac

To delete leftover sensitive files or shred previously deleted data on your Mac, you can wipe the free space on your hard drive or SSD.

Here are a few options to securely overwrite free space:

  • Disk Utility – Open Disk Utility, select your drive, choose Erase Free Space button
  • Terminal – Use diskutil secureErase freespace command
  • Third-party apps – Apps like Eraser for Mac can wipe free space

This will shred leftover bits of sensitive documents, passwords, images, financial data, or internet history that may be lurking in your free space.

How to Permanently Delete Applications on Mac

To remove unwanted applications from your Mac:

  1. Drag to Trash – Drag the app to Trash from Applications folder
  2. Delete from Launchpad – Delete the app icon from the Launchpad screen
  3. Use Uninstaller – Use a third-party uninstaller app to delete remnants
  4. Look for receipt – Check ~/Library/Receipts for the .pkg file and move it to Trash

This will delete the application so it no longer shows up in your Applications or Launchpad. However, some support files may persist in the Library folders.

For a more thorough uninstall, use an app like OnyX or AppCleaner to delete all associated files.

Completely Remove Leftover Files/Data on Mac

After wiping your Mac hard drive, there may still be leftover hidden files and folders containing your data in the Library directory.

To check for these, open Finder and press Shift+Command+G to open the Go To Folder dialog. Enter the following paths to check for any leftover user-generated files:

  • ~/Library
  • /Library/Application Support
  • /Library/User Pictures
  • /Library/Mail Downloads
  • /Users/Shared

Any leftover files should be deleted. You can also type sudo rm -rf [path] in Terminal to delete stubborn folders.

Additionally, check for these system-level items that may contain personal data:

  • Keychains – Delete these in Keychain Access
  • iCloud data – Sign out of iCloud
  • Cached messages – Open Messages app > Preferences > Accounts > Delete

This will help ensure no traces of your old user data are left behind.

Restart Your Mac in Recovery Mode

As a last step, restart your Mac into macOS Recovery:

  1. Restart Mac and hold Command + R
  2. Select Disk Utility
  3. Erase Macintosh HD drive using Most Secure option
  4. Quit Disk Utility
  5. Reinstall macOS clean install

This final wipe and reinstallation will remove any last traces of your data for a fully wiped Mac.

Conclusion

There are a few different approaches to deleting everything on a Mac, depending on your specific needs:

  • Erase All Content and Settings – Deletes user accounts and data and reinstalls macOS
  • Erase Mac and Revert to Factory Settings – Completely wipe and restore to original factory OS
  • Secure Erase Free Space – Overwrites deleted and free space to shred leftover data
  • Start Up From External Drive – Boot from another drive to wipe main internal drive
  • Use Target Disk Mode – Connect Mac drive to another computer and wipe from there

The most thorough approach is to boot into Recovery mode, securely erase the hard drive, reinstall macOS, and delete any leftover data or files.

Following these steps will completely wipe your Mac back to a clean state with no personal data left behind.