How to properly dispose of your hard drives

3 min read
Lexie

Hi, I'm Lexie! I write about information security, Bitcoin, and privacy.

An image of a laptop shaking its contents into the bin.

Data is valuable. Your pictures, legal documents, chat logs, and even saved video games are all things you wouldn’t want to be public.

Today, people generally go to great lengths to protect data, but devices age and don’t last forever. When we need to replace them, we often don’t think about what happens to the data that is still on the drive, and how people might be able to access it.

Most computers have a hard disk drive, or HDD, which are disks coated with a magnetic metal layer. They rotate similar to a CD or vinyl record and read by a sensor at the tip of an arm.

HDDs are very sensitive, and data can persist on them in various ways. When disposing of an HDD, it’s important to make sure no one can still access the data on it.

Fortunately, we have a variety of options to wipe HDDs, the most reliable of which is a combination of digital and physical tools. If your computer has an HDD, make sure to read this guide before getting rid of it, no matter if you sell or dispose of it.

1. Encrypt your HDD as soon as you buy it

Always encrypt all information on your hard drive. Modern operating systems should do this, but it’s best to double check if your operating system enables disk encryption by default.

Check the Mac OS, Windows 10, and Ubuntu support guides to see how to encrypt your HDD (the same methods should also work for external hard drives). You could also use Veracrypt, which is a cool cross-platform tool to encrypt drives and data.

Make sure you encrypt your data with a secure password, one long and complicated enough that it can’t be brute forced by somebody with a lot of computing power.

2. Wipe your HDD before you sell it

Additionally, you can wipe your HDD by reformatting it. Nearly all operating systems have built-in tools that can wipe your drive, though they all have their own proprietary name:

  • Disk Management in Windows
  • Disk Utility in Mac OS
  • Disks in Ubuntu

Ideally, go through the wipe process three or four times to make sure the data of your disk is unrecoverable.

3. Disassemble and destroy your HDD!

In case you want to be extra sure about leaving no trace, or in case your hard drive cannot be easily encrypted, reformatted, and wiped (e.g., if it’s broken), you will need to render the drive unusable physically. That is, smash it!

Firstly, you need to get the shiny metal disks from within the HDD case. Usually, this involves unscrewing a few screws, but as long as you don’t intend to put it back together, feel free to use whatever force is necessary.

Once you get the metal disks, there are a variety of options to destroy them. Be careful with splinters and sharp edges, and always wear appropriate clothing, such as gloves and safety goggles!

Use a hammer

The most accessible tool to destroy a hard drive is the hammer. Anything that deforms the disk, or cracks or punches holes in it, will make it significantly harder to access any data stored on the device.

Drill it

You can drill holes into your HDD to make sure it never turns again. But this also requires you to carefully fix the disk in a way you can safely hold a drill against it.

Magnets!

Not any magnet will do, but if you have access to strong rare-earth magnets, they will scramble the data on the disk beyond recognition.

Shred it

By far the most effective way to destroy a disk is to shred it. Your office paper shredder won’t be up for the task, but maybe a junkyard nearby will let you borrow theirs?

Dissolve it

Battery acid or something similar will dissolve the thin coating that stores the data. Only employ this method if you have the appropriate training to handle acid!

Preventative measures to protect your drives

When buying a new disk drive, you should encrypt it straight away to protect it against abuse if you lose or sell it.

Though it makes sense to destroy HDDs when you finish with them, there’s no need to obliterate SDDs. Encrypting and wiping your SDD is the only way to get rid of its contents.

Lexie is the blog's resident tech expert and gets excited about empowerment through technology, space travel, and pancakes with blueberries.