If you’re getting rid of an old computer or upgrading your hard drive or SSD for something bigger, faster, or just newer, you need to make sure your data is wiped clean from your old hardware. Why? Because if you don’t, someone else could easily get hold of the drive and look at all of your personal files and folders.
Before you smash your old drive to pieces, the first thing you should do is back up anything important on it. Any family photos, work documents, financial details, emails — whatever data is important to you. You can transfer it to an external drive, send it to a cloud storage provider, or clone the drive entirely. However you do it, make sure you do so before looking into wiping the drive as the last thing you want to do is forget and find yourself trying to piece your destroyed drive back together afterward in an attempt to recover it.
Wipe a drive on Windows
Step 1: Download Eraser
There are a number of applications that will do a good job of wiping your hard drive or SSD, but Eraser is our favorite. It’s free, intuitive, and comprehensive. Since it needs to run within Windows you can’t wipe the drive you’re running it from. If you don’t have an alternative drive to boot from, you might want to consider an alternative tool like DBAN.
Download Eraser from the official site and install it as you would any other application.
Step 2: Create task
Open the Eraser application and right-click (or tap and hold) in the main Erase Schedule window and select New Task. In the window that appears, make sure Run Manually is selected and then select the Add Data button at the bottom of the window. Change the Target Type to your drive of choice.
Step 3: Select an erasure method
There are a number of erasure methods to choose from each with their own particular benefits. To keep things simple, a Pseudorandom Data (1 pass) is sufficient for basic personal information and SSDs. However, if you’re wiping a hard drive or are concerned about anything particular being recovered from your drive, more passes means less of a chance of that data being recoverable, so pick one with more passes for greater peace of mind, if you prefer.
Step 4: Run the task
Although you can set up tasks to run automatically or at a scheduled time, we’ve set this one up manually to give us a chance to double check everything. Make sure any data you can’t afford to lose is safely backed up and that you have selected the right drive and erasure method for this task.
When you’re certain everything is ready, right-click the task in Eraser and select Run Now.
What about Windows reset?
Windows 10 does include its own reset options which claim to wipe drives relatively effectively. While we would still recommend using third-party software like Eraser, the Windows reset and format method is still effective if you take a couple of extra steps. To make sure your data is not only deleted but overwritten and unrecoverable, follow our Windows reset guide, and then fill the drive up with data. You can do so by copying movie files, game installs, or anything that is particularly large — think hundreds of megabytes or multiple gigabytes. Copy and paste them over and over again until the drive is full. Then reset it again.
The drive should then be clean enough to dispose of.
Wipe a drive on MacOS
Step 1: Run Disk Utility
MacOS’ built-in disk erasure tool is fantastic and more than enough for the average hard drive wiping. Access it by booting to MacOS Recovery by turning your Mac on and holding Command + R. Continue holding until you see the Apple logo or a globe. The MacOS utility window should open shortly after.
From the list of options, select Disk Utility.
Step 2: Choose the disk to erase
Select View from the top menu bar, followed by Show All Devices. Using the left-hand menu, select the disk you want to erase.
Step 3: Choose the erase options
Select the Erase tab in the top menu. Select the new name for the volume after it’s been erased. Choose the APFS format unless you plan on installing a version of MacOS before High Sierra on the drive afterward (in which case select Mac OS Extended). For the Scheme choose GUID Partition Map.
If you’re erasing an SSD, skip on to the next step. If you’re using an HDD, you can make the erasure a little more effective. To do so, select Security Options and use the slider on the ensuing page to change the number of passes that the erasure tool makes over the drive. More than one is enough, and anything over three is probably overkill.
Step 4: Erase the data
If you’re sure that you’ve backed up all of your important data (there’s no going back after this step) select Erase.
Physically destroy the drive
An alternative step to the above digital method of removing data, or a secondary one if you want to make doubly sure your data isn’t recoverable by anyone, is to physically destroy the drive.
If you’re the handy type, you can pull the hard drive platters – the actual disks that the zeros and ones that make up your data are stored on — and sand the surface or hammer them until they look all dimpled and cratered. Another option is to take a rare-earth magnet such as a neodymium magnet, and run it over the drive platter. That will deform it and make any data on it unreadable.
You could also drill holes in the drive if you don’t want to go to the trouble of removing the enclosure.
There are companies that will professionally shred the drive for you while you watch too. Think “will it blend,” but with a much bigger blender.