Making sure that your personal information is safely and securely erased from devices that you are no longer using is a good thing. Here's a quick guide to securely wiping hard drives (HDDs), solid state drives (SSDs), flash drives, and even iOS and Android devices.
Just bear in mind that these erasure methods are permanent, and there's no undo. If you don't have a backup of your data, it's gone forever.
Yes, you can wipe a drive using the Windows format command.
Fire up a Command Prompt and type:
Format volume /P:passes
Where volume is the drive letter, and passes is the number of format passes you want to make.
To wipe d drive with 4 passes, use the following:
Format d: /P:4
Under Windows 8 and Windows 10, the wipe passes use random numbers to overwrite data on the disk (on previous versions 0 were used).
You can also wipe the drive that Windows is installed on by booting from a Recovery Drive and choosing the Troubleshoot > Advanced options option to access Command Prompt.
Build your own $20,000 Windows 10 workstation
Built-in way to erase iOS and Android devices
iOS and Android devices both have built-in tools to erase the devices.
On iOS: Settings > General > Reset and then tap Erase All Content and Settings.
On Android: Settings > Backup & reset > Factory data reset and then tap Reset phone or Reset device.
You can also securely wipe the devices remotely using Find My iPhone for iOS or the Google Account associated with the Android device.
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The hands-on method
Not sure how to erase a device? I guarantee you that if you get a big enough hammer and spend enough time hammering, this will work on anything!
This method also works great if you just want to destroy drives before you take them to the recycling plant. It's also a great stress reducer.
You will need:
A hammer (I use my trusty 32oz "fine adjustment" hammer)
A thick nail (a 6-inch nail will do fine)
Thick gloves -- because you're going to be hammering that nail through the drive using the hammer, and hammers seem to be magnetically attracted to thumbs
A block of wood -- so you don't nail the drive through your floor (it's preferable to do this outside if you can)
Eye protection -- you've only got a maximum of two to start with, so it's silly to take chances!
Now you apply brute force. Ideally you want to put a nail through the platters of the drive, going all the way through (it's actually not as hard as it sounds). I aim for the spot marked by the red Xs on hard drives.
Alternatively you can use a power drill to make holes, but make sure that you have a way to securely hold the drive, for example, using a vice. Don't hold the drive in your hand because if the drill bit catches and the drive starts to spin -- or "helicopters" -- on the end of the drill then there's a real risk of injury.
Another thing to bear in mind is that the data in SSDs is held on small flash storage chips rather than large platters, and to securely erase the data you need to smash the chips. Usually, this means taking the cover off the drive before you start swinging.
If you're not sure which are the flash storage chips, just drive a nail through all the large chips to be on the safe side.
Apricorn Aegis Fortress L3 portable storage drive
What about storage that's defective but under warranty?
The time that wiping storage devices gets complicated is when the device is broken or malfunctioning in some way.
For example, a hard drive that dies, or a storage card that can no longer be accessed.
What do you do if you have to return something under warranty but there's data stored on the device?
Well, things get complicated.
You could rely on the face that the device is dead, and that your data is inaccessible, but that's probably not the case. Data can be recovered off most storage devices if you are willing to throw money at the problem. You might not be able to get access to it, but someone else could.
Another option open to for many devices is to encrypt all your data. If the data on your PC, external storage, or flash drive is encrypted (and the encryption is legit, and assuming you've chosen strong passphrases and the like), then the data is likely unrecoverable to third parties.
Use high-end storage with built-in data destruct features
High-end encryption devices -- such as the Apricorn Aegis Secure Key 3z -- will have a built-in data destruct feature where you enter a PIN code or run a program that will securely wipe the device.
PIN code data destruction is especially handy because after you enter the PIN the device destroys the encryption key and appears blank when it boots up, offering plausible deniability.
StarTech 4-bay drive eraser
If you have a lot of drives to erase, you need a professional piece of kit that can keep up with the demands that you're going to place on it.
This hard drive eraser provides standalone, simultaneous drive erasing for up to four 2.5-inch or 3.5-inch SATA hard drives or solid-state drives.
Unlike hard-drive docking stations or adapters that require a computer connection and software to erase drives, this hard drive sanitizer features standalone erasing that doesn't require a host computer. This avoids the hassle of connecting your drives to a host computer and protects your drives from external security threats like remote data access.
The four-bay design maximizes efficiency by batching multiple drives in single erase projects, saving you valuable time. The hard drive eraser supports USB 3.0, also known as USB 3.1 Gen 1, with file transfer rates of up to 5Gbps.
This is the default tool that most people who have the odd drive to erase turn to. I've used this tool to wipe thousands of drives and found it to be both thorough and very effective.
While DBAN is an awesome tool, it's important to understand its limitations. Here is what the new owners of DBAN, Blancco Technology, have to say:
"While DBAN is free to use, there's no guarantee of data removal. It cannot detect or erase SSDs and does not provide a certificate of data removal for auditing purposes or regulatory compliance. Hardware support (e.g. no RAID dismantling), customer support and software updates are not available using DBAN. Should you need to erase data from a SSD or require a certificate of data removal, request a free trial of Blancco Drive Eraser."
Blancco mobile and phone wiping software allows organizations, mobile service providers and resellers to permanently erase all data from smartphones and tablets running on iOS, Android, Windows Phone and BlackBerry operating systems.
Securely wipes iOS, Android, Windows Phone and BlackBerry operating systems
Quickly erases data on up to 50 mobile devices simultaneously
Automatically selects the fastest and most effective data erasure method
Provides digitally signed certificate of proof of data erasure for audit trail purposes
Compliant with state, federal and international data privacy regulations and guidelines, including ISO 27001 and ISO 27040
The WiebeTech Drive eRazer Ultra is a stand-alone device that completely and quickly cleans hard drives. Simply connect a drive to the Drive eRazer Ultra and it will sanitize the drive faster than using software, and without tying up your computer.
The Drive eRazer Ultra leaves the drive ready for safe re-use, and comes with a dozen different preset erase procedures, including US Department of Defense graded methods for data wiping.
Simple setup and operation with LCD and menu buttons
USB port for drive previewing and deletion confirmation
One of the easiest -- and certainly the cheapest -- ways to erase data on a device is to encrypt the entire drive with a complex passphrase. You can use built-in tools such as BitLocker on Windows or FileVault on macOS, or a third-party tool such as VeraCrypt. Encrypt the drive with a strong throw-away passphrase and you're done.
No passphrase, no data.
You can then format the drive, from which point it should be sterile and ready to accept a reload of the data.