Quick Summary
Wiping your hard drive involves overwriting all of the data on it with random bits of data to make your files unrecoverable. There are a few methods you can use:
- Use built-in Windows tools like Diskpart’s clean command or the Format option
- Use third party software like DBAN, Eraser, or KillDisk
- Remove the hard drive and physically destroy it
Wiping your drive ensures your personal files cannot be recovered if the computer ends up in the wrong hands. It’s an important step to take before disposing of, selling, or donating your computer.
Why Should I Wipe My Hard Drive?
When you delete files or reformat your hard drive, the data isn’t actually erased – only the references to those files are removed. The actual data remains on the drive and could still be recovered with the right tools.
So if you dispose of, sell, or donate your computer without wiping the hard drive, there is a risk that someone could steal your personal information. Identity thieves look for opportunities like this.
You should wipe your drive to ensure things like:
- Personal photos and videos
- Financial information
- Legal documents
- Saved passwords
- Private communications
- Sensitive work data
Cannot be accessed by whoever ends up with your old computer next. Wiping your drive gives you peace of mind that your personal data has been securely removed.
How Does Drive Wiping Work?
Wiping works by overwriting the existing data on a hard drive. Even if you reformat your drive or delete files, remnants of that data still exist until they get overwritten with new bits of data.
Drive wiping overwrites all of the existing data with random strings of 1s and 0s so that the original data cannot be recovered. The key is that is uses multiple passes – writing over the same disk space again and again.
There are different standards that specify exactly how many overwrite passes are required to fully wipe a drive. For example:
- The U.S Department of Defense 5220.22-M standard requires 7 passes
- The Gutmann standard uses 35 passes
- Many tools use 3-7 passes by default
With each pass the existing data becomes harder and harder to recover. Doing multiple overwrite passes ensures all old data gets completely erased.
Overwrite Methods
There are a couple methods used to do the overwrite passes:
Zeroes and Random Data
Many tools will do a pass writing all zeroes to the drive first. Subsequent passes then write random data like 1s and 0s. The randomness ensures maximum wiping.
Custom Patterns
Tools like DBAN offer the ability to create custom overwrite patterns. You can choose strings of characters or numbers to use instead of purely random data.
Gutmann Method
The Gutmann method is a complex 35 pass pattern specifically designed to make data recovery as difficult as possible. It writes carefully selected data patterns designed to maximize the overwrite effectiveness.
While overkill in most cases, it’s still an option with certain wiping tools. A few passes of random overwrites will suffice for most home users though.
How Long Does Drive Wiping Take?
Wiping a hard drive can be a lengthy process depending on the method you choose and your drive’s size. For example:
- A single pass could take 2-3 hours for a 1TB hard drive.
- A 7-pass wipe of a 500GB drive could take up to 14 hours.
- A 35-pass wipe with the Gutmann method could take days.
Be prepared to let the wiping tool run overnight if you have a large drive and want to do several passes. Also keep in mind:
- Larger hard drives take longer to wipe.
- More passes equals more time.
- Faster hard drives get wiped quicker.
- SSDs can wipe very quickly with their faster write speeds.
The wiping software will usually show you the estimated completion time so you know what to expect.
Built-in Windows Drive Wiping Tools
You actually have a couple options for wiping your hard drive right from within Windows itself.
Using Diskpart’s Clean Command
Diskpart is a command line disk partitioning utility included with Windows. The “clean” command it offers performs a basic wipe of a selected disk.
To use it:
- Open the Command Prompt as administrator
- Type “diskpart” and hit enter
- Type “list disk” to show disks
- Select your disk by typing “select disk X” (replace X with disk number)
- Type “clean” to start wipe
This performs a single pass wipe filling the drive with zeroes. It won’t take as long as a multi-pass wipe with a third party tool, but still gets the job done if you just want a quick wipe.
Using Format in File Explorer
You can also right-click your hard drive in Windows File Explorer, select Format, and perform a full format to wipe the drive.
This performs a similar single pass zero wipe to the Diskpart clean method. It’s less flexible than specialized wiping software but handy if you just want to do a quick built-in wipe.
Keep in mind that both these methods only do a single wipe pass. They are quick but won’t render your data completely unrecoverable like a multi-pass approach.
Wiping Your Drive From BIOS
Some computers support drive wiping from the BIOS. For example, many HP laptops have a “F10” option when booting that loads into a hardware diagnostics menu.
From there you can select hard drive tools and choose to sanitize your drive. This performs a multi-pass wipe similar to using third party software.
Check your manufacturer’s support site for details on accessing this low-level BIOS drive wiping if available on your machine. It’s convenient not needing bootable media.
Booting From a Wiping CD or USB
For the most reliable wipe, you’ll want to boot your computer from a CD/DVD or USB drive that contains wipe tools. This allows the wipe to run outside of your installed OS.
Popular options like DBAN can be burned to a CD or loaded onto a USB stick. You can then configure the wipe settings before booting from the media to run it.
The steps involve:
- Download and install the wiping software ISO file
- Burn it to a CD/DVD or copy to a USB drive
- Restart your computer and boot from the media
- Configure and start the wiping process
This ensures that no locks or data in use issues interfere with wiping your hard drive fully.
Web Browser Based Wiping
Some drive manufacturers also offer browser-based wiping tools. For example:
- Western Digital has an Erase tool.
- Seagate offers a DiscWizard wipe option.
- Samsung provides a SSD Magician Secure Erase.
You run these after booting from a CD/USB drive, connect to wifi, and open the browser-based utility. This allows starting a wipe without installing software.
Check your drive maker’s site for details on any browser-based wiping tools they offer. It’s often tailored specifically to wiping their drives.
Third Party Drive Wiping Software
For maximum security, dedicated third party drive wiping utilities are recommended. Some of the top options include:
DBAN
Darik’s Boot and Nuke (DBAN) is one of the most widely used and trusted drive wiping tools. It boots from CD/DVD/USB and provides multiple options:
- Multiple wipe methods from a single pass to many passes
- Ability to wipe full drive or just partitions or free space
- Supports various international standards like DoD 5220.22-M
- Customizable wipe patterns
- Wipes hidden sectors and slack space
DBAN is free, open source, and continually updated. It supports wiping IDE/SATA/SCSI/NVMe drives.
Eraser
Eraser is another popular free and open source drive wiping utility. Features include:
- Schedule wipe tasks or run immediately
- Verify wipes to ensure completion
- Supports US Department of Defense 5220 and Peter Gutmann wipe standards
- Can wipe individual files as well as full drives
- Provides detailed reporting once complete
Eraser wipes HDDs, SSDs, and external media like USB drives. It works on Windows and some Linux systems.
KillDisk
KillDisk is commercial disk wiping software that offers advanced features like:
- Certified data sanitization for government/military agencies
- Up to 50 wipe passes
- Very fast SSD wiping
- Command line interface for wiping servers
- Integrates with desktop tools for easy use
KillDisk supports all types of drives and has wiping options compliant with US standards like DoD 5220.22-M and NAVSO P-5239-26.
SDelete
SDelete is a free secure delete tool from Microsoft Sysinternals that integrates with the Windows Explorer context menu for easy wiping of selected files and folders.
Key features:
- Single pass zero wipe
- Multiple wipe options
- Shred unused disk space
- Supports DoD 5220.22-M wiping
While light on features, it’s easy to use and handy for quickly wiping selected files or empty space.
WipeFile
WipeFile is another handy free file wiping tool for Windows. It sits in your system tray and lets you easily wipe files, folders, or empty disk space to prevent recovery.
Key features:
- Drag and drop files/folders to wipe
- Set automated wiping of browser temp files
- Wipe unused space on a drive or partition
- Multiple wipe passes and standards
- Lightweight and easy to use
WipeFile is a great option for selectively wiping sensitive files while leaving others intact.
Physically Destroying Hard Drives
For the most thorough data destruction, you can physically dismantle or destroy old hard drives. This provides complete assurance that no data could ever be recovered.
Some physical destruction methods include:
- Drilling holes – Drill multiple holes through the hard drive circuit board and platters to destroy the internal components beyond repair.
- Shredding – Use a specialty shredder designed to shred hard drives and other e-waste.
- Degaussing – Use powerful magnets to disrupt and erase data stored on platters.
- Crushing – Crush drives with a press or hammer to completely obliterate the drive.
- Incineration – Physically burn hard drives to destroy the drive internals using extreme heat.
Keep in mind that physical destruction may be prohibited under some data security policies or local e-waste recycling regulations. But it provides the most surefire data destruction in many scenarios.
Quick Drive Wiping Tips
Some pointers to ensure successful wiping:
- Back up any data you need to keep first
- Disconnect the drive you want to wipe
- Use third party tools for multiple wipe passes
- Boot from the wiping CD/USB drive for best results
- Verify the tool completed successfully
- Safely dispose of the wiped drive afterward
With disks being so large now the wiping process can take many hours to complete. Be patient and let it finish fully before disposal.
Next Steps After Wiping Your Drive
Once your drive wipe is complete, now what? Here are some tips on safely disposing of the drive:
- Destroy it physically if policies allow and local e-waste laws permit
- Safely recycle the drive at an e-waste disposal event
- Donate to charity groups that refurbish old computers
- Sell or give away to family and friends if fully wiped
Just don’t throw an unwiped drive in the regular trash! Follow your local regulations for electronics disposal and recycling to keep sensitive data out of the wrong hands.
Conclusion
Wiping your hard drive before disposal is a simple but critical security step when getting rid of an old computer. It ensures sensitive files don’t fall into the wrong hands.
Make sure to use dedicated drive wiping tools like DBAN and perform multiple overwrite passes for maximum safety. Physically destroying the drive is also an option if permitted by applicable regulations.
Following proper drive wiping and disposal procedures gives you real peace of mind that your personal data will never come back to haunt you down the road.