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    How to Wipe a Computer Clean of Personal Data

    Before selling, donating, or recycling your outdated laptop or desktop, protect your privacy with this important step

    Computer with sponge wiping screen clean Photo Illustration: Lacey Browne/Consumer Reports, iStock

    Got an old laptop or desktop computer laying around? By selling it or donating it to someone, you can clear up space in your home, maybe earn a little cash, and extend the computerā€™s useful life.

    But how do you keep the next owner from accessing all the photos, financial documents, and other private data you had stored on the computer?

    Short of removing the hard drive (which you could do, but then the next owner would have to install a new drive), the best solution is to perform whatā€™s known as a factory reset, which technically wipes the drive clean of personal data.

    Why canā€™t you simply delete your Downloads folder, log out of your accounts, and call it a day?

    More on Computers

    ā€œYouā€™re likely to forget things like passwords saved in browsers and personal data in the deleted items folder,ā€ says Matt Ham, owner of the service company Computer Repair Doctor. ā€œOr you can miss deleting some important files altogether. Reinstalling your system before sale is a much safer alternative.ā€

    While a factory reset is generally sufficient, a determined hacker could, at least theoretically, use advanced data recovery software to retrieve your old files.Ā 

    If thatā€™s a significant concernā€”maybe youā€™re planning to sell the device to a stranger on eBayā€”go ahead and remove the hard drive, says Richard Fisco, who oversees electronics testing for Consumer Reports.Ā 

    After all, a hacker canā€™t break into a hard drive thatā€™sĀ not there.

    ā€œThe gold standard in hard drive security consists of using a pointy nail and a few swift swings of a hammer,ā€ Fisco says half-jokingly. ā€œJust make sure youā€™re wearing safety glasses.ā€

    And before performing a factory reset (or, perhaps, breaking out the hammer and nails), be sure to back up any important data on the computer to another drive or to the cloud. Once thatā€™s done, and youā€™ve verified that the data has been safely backed up, carrying out a factory reset is simple, whether youā€™re on a, Mac, Windows PC, or Chromebook.

    Apple Users

    The steps for resetting the device vary slightly depending on whether your Mac has an M-series processor or an Intel processor. Apple has phased out Intel processors since 2020 in favor of its own homegrown M1 and M2 chips.Ā 

    If you donā€™t know which one you have, simply click on the Apple menu in the top left corner of the computerā€™s screen, then click About.Ā 

    Before you begin the reset, be sure to back up any important files and then sign out of iCloud. That can be done in the Apple ID section of the System Preferences app.

    You should also copy your keychains to a flash drive. This step isnā€™t required, but transferring those account names and passwords onto your new machine will save you the hassle of reentering the WiFi password at the local coffee shop or the log-in info for online retailers.

    To perform a factory reset on a Mac with an Apple M-series processor, youā€™ll first want to turn it off. Then turn it back on while holding down the power button. Eventually, a screen will appear featuring a black background and two icons: your hard drive (called Macintosh HD by default) and Options. Click Options.

    At this point, you may be asked to input your username and password. Once thatā€™s done, click Disk Utility > Hard Drive (again, called Macintosh HD) in the left sidebar > Erase. Youā€™ll be prompted for a new name (we recommend Macintosh HD, just for the sake of simplicity) and Format (which should be APFS).

    Now click Erase Volume Group, enter your Apple ID when prompted, then click Erase Mac and Restart. Youā€™ll then follow the onscreen instructions, which include things like your language and WiFi password.

    The steps are similar if you have an Intel-based Mac.

    Hold down the Command + R keys while starting up your Mac and enter your password when prompted. Click Disk Utility on the next window and click Continue. Then click Macintosh HD in the left sidebar and Erase in the toolbar. Select MacOS Extended (Journaled) format and quit Disk Utility when the process ends.

    To finish the reset, navigate back to the Utilities window and choose Reinstall MacOS to reinstall the original operating system.

    After the reinstall, the Mac will begin the setup process. This should look familiar if youā€™ve set up this computer before. If youā€™re selling your computer, you can skip setup by pressing Command + Q and let the new owner complete that process.

    Windows Users

    Before beginning the factory reset process, back up all important files. You might also want to make sure that you have the serial numbers and/or usernames and passwords for any registered apps handy for when you go to reinstall them later.

    The process for resetting your PC differs slightly for each version of the operating system.Ā 

    For Windows 11, click Start > Settings > System > Recovery > and then click Reset This PC. Youā€™ll then follow the onscreen instructions.

    For Windows 10, go to the Start Menu and click on Settings. Then navigate to Update & Security, and find the Recovery menu. Next, select Reset this PC and choose Get Started. Follow the instructions to revert your computer to when it was first unboxed.

    Chromebook Users

    Chromebook users have the easiest time wiping their laptops. Unlike Apple and Windows users, they already have most of their files stored online in Google Drive. So thereā€™s little to back up before you begin the process.

    Youā€™ll first want to sign out of your Chromebook. Then type and hold Ctrl + Alt + Shift + R, then select Restart. In the window that pops up select Powerwash and then continue.

    This will prompt a restart, which will flush away all your personal information.

    If youā€™re ready to sell or donate the computer, donā€™t log back inā€”the next person who logs in becomes the Chromebookā€™s primary user.


    Headshot image of Electronics editor Nicholas Deleon

    Nicholas De Leon

    I've been covering consumer electronics for more than 10 years for publications like TechCrunch, The Daily (R.I.P.), and Motherboard. When I'm not researching or writing about laptops or headphones I can likely be found obsessively consuming news about FC Barcelona, replaying old Super Nintendo games for the hundredth time, or chasing my pet corgi Winston to put his harness on so we can go for a walk. Follow me on Twitter (@nicholasadeleon).