Guides

How to Wipe a Hard Drive Before Selling Your Computer

Selling your old computer is a smart way to recoup some value when you upgrade, but handing over a machine full of personal data is a serious privacy risk. Studies have found that over 40% of secondhand drives sold on eBay and Craigslist still contain recoverable personal files, including tax returns, medical records, and saved passwords. A quick format is not enough. Before you list that laptop or desktop on any marketplace, you need to properly erase your data.

Key Takeaways:

  • Back up your files and deauthorize all accounts before you wipe anything
  • Windows "Reset This PC" with the clean data option is the simplest method for most sellers
  • SSDs and HDDs require different erasure approaches — do not treat them the same
  • Always verify the wipe was successful before handing over your device
  • Reinstall a fresh OS to maximize resale value and give the buyer a working machine

Before You Wipe: The Pre-Sale Checklist

Wiping your drive is the main event, but skipping the prep work can leave you locked out of your own accounts or missing important files. Run through this checklist before you erase anything.

1. Back Up Everything You Want to Keep

Copy your documents, photos, videos, downloads, and desktop files to an external drive, cloud storage, or both. Check these commonly overlooked locations:

  • Desktop and Downloads folders — where most people dump files
  • Browser bookmarks and saved passwords — export from Chrome, Firefox, or Edge settings
  • Email archives — if you use a desktop email client like Outlook or Thunderbird
  • Application data — game saves, creative project files, local databases
  • SSH keys and credentials — in your user profile's .ssh folder if you use them

2. Deauthorize Software and Accounts

Many apps limit the number of devices you can use. Deauthorize before wiping so you do not waste an activation:

  • iTunes/Apple Music — Account > Authorizations > Deauthorize This Computer
  • Adobe Creative Cloud — Sign out (this deauthorizes the device)
  • Microsoft Office — Sign out of your Microsoft account in any Office app
  • Antivirus software — Deactivate or transfer your license
  • Any subscription software with a device limit

3. Sign Out of Everything

Sign out of all accounts on the computer — web browsers, cloud storage clients (OneDrive, Google Drive, Dropbox), messaging apps, and gaming platforms (Steam, Epic, Xbox). Simply wiping the drive handles this at a data level, but signing out first also removes the device from your account's recognized devices list on the service side.

4. Unpair Bluetooth Devices

If you paired a keyboard, mouse, or headphones, unpair them before wiping. These pairings are stored on the computer, and the new owner does not need a record of your devices.

5. Identify Your Drive Type

The correct wipe method depends on whether your computer has a traditional hard disk drive (HDD) or a solid-state drive (SSD). To check on Windows, open Task Manager, click the Performance tab, and select your disk — it will say "HDD" or "SSD." On a Mac, click the Apple menu, choose About This Mac, then Storage. Most laptops made after 2016 have SSDs. This distinction matters because SSDs and HDDs require fundamentally different erasure approaches.

Wiping a Windows PC

Windows 10 and 11 both include a built-in reset feature that works well for resale, especially on computers with SSDs.

Windows 11

  1. Open Settings > System > Recovery
  2. Click Reset this PC
  3. Choose Remove everything
  4. Select Local reinstall (faster) or Cloud download (fetches a fresh copy from Microsoft)
  5. Click Change settings and toggle Clean data to Yes — this is the critical step that overwrites data instead of just deleting file pointers
  6. Confirm and let the process complete. This can take 1 to 3 hours.

For a detailed walkthrough with screenshots, see our Windows 11 wipe guide.

Windows 10

  1. Open Settings > Update & Security > Recovery
  2. Under Reset this PC, click Get started
  3. Choose Remove everything
  4. Click Change settings and enable Data erasure (labeled "Clean data" in newer builds)
  5. Confirm and wait for the process to finish

Our Windows 10 wipe guide covers this process in full detail.

When the Built-in Reset Is Not Enough

The Windows reset with clean data enabled works well for SSDs because it triggers the drive's internal erase functions. For older desktops with traditional HDDs, you may want a dedicated wipe tool for extra confidence. DBAN is a free bootable tool that overwrites every sector of an HDD. You boot from a USB drive, select the disk, and choose a single-pass wipe — that is all it takes.

If you want a tool that provides a certificate of erasure (useful if you are selling a business computer), BitRaser Drive Eraser generates a tamper-proof erasure report that proves the data was destroyed. This is overkill for most personal sales, but valuable for business equipment.

Bottom Line: For most people selling a personal Windows computer, the built-in "Reset This PC" with the clean data option is the fastest and simplest method. It works, it is free, and it leaves a clean OS ready for the buyer.

Wiping a Mac

Apple has made secure erasure straightforward on modern Macs, though the process differs slightly depending on your hardware.

Apple Silicon Macs (M1, M2, M3, M4) and Intel Macs with T2 Chip

These Macs encrypt the drive by default with hardware encryption. Erasing the encryption key makes the data unreadable instantly.

  1. Open System Settings > General > Transfer or Reset
  2. Click Erase All Content and Settings
  3. Enter your administrator password
  4. Sign out of your Apple ID when prompted
  5. Confirm the erase

This process takes just a few minutes and leaves the Mac at the setup screen, ready for the new owner.

Older Intel Macs (No T2 Chip)

For pre-2018 Intel Macs without a T2 security chip:

  1. Restart and hold Command + R to boot into macOS Recovery
  2. Open Disk Utility
  3. Select your startup disk (usually "Macintosh HD")
  4. Click Erase
  5. Choose APFS or Mac OS Extended (Journaled) as the format
  6. For HDDs, click Security Options and select at least a one-pass overwrite
  7. After erasing, close Disk Utility and choose Reinstall macOS from the recovery menu

For a deeper walkthrough including FileVault considerations, read our Mac wipe guide.

Wiping External and Secondary Drives

If you are selling a desktop that has additional internal drives, or if you are including an external hard drive or USB drive with the sale, each one needs to be wiped separately. The OS reset only covers the system drive.

External HDDs

On Windows, you can use a free tool like KillDisk Free to overwrite an external hard drive while your system is still running. On macOS, use Disk Utility's Erase function with Security Options set to at least one pass.

External SSDs

For external SSDs, a simple full format (not quick format) in Windows or the standard Erase function in macOS Disk Utility is sufficient. External SSDs connected via USB typically do not support the ATA Secure Erase command, so a full format combined with TRIM is the best available option through a USB connection.

USB Flash Drives

A full format (not quick format) through Windows or macOS will overwrite the data on a USB flash drive. In Windows, right-click the drive in File Explorer, choose Format, uncheck "Quick Format," and click Start. On macOS, use Disk Utility to erase the drive.

Verifying the Wipe Was Successful

Do not just trust that the wipe worked — verify it. This step takes five minutes and gives you confidence before handing over the device.

Quick Visual Check

Boot the computer after wiping. You should see either the OS setup screen (if you reinstalled) or a "no operating system found" message (if you wiped without reinstalling). If you see your old desktop with your wallpaper and icons, the wipe did not work. Start over.

File Recovery Test

For extra assurance, download a free file recovery tool like Recuva (Windows) or TestDisk (cross-platform) and scan the wiped drive. If the tool finds zero recoverable files, or only finds meaningless file fragments with no readable content, your wipe was successful. If it finds intact personal documents, photos, or other recognizable files, you need to wipe again with a more thorough method.

Our guide on whether data can be recovered after a secure erase explains the technical details behind verification.

Reinstalling the Operating System for Resale

A wiped computer with no operating system is worth less than one with a fresh, working OS. Most buyers on eBay, Facebook Marketplace, and Craigslist expect a ready-to-use machine. Reinstalling takes 20 to 45 minutes and meaningfully increases your selling price.

Reinstalling Windows

  1. On another computer, download the Microsoft Media Creation Tool and create a bootable USB installer
  2. Plug the USB into the wiped computer and boot from it (you may need to press F12, F2, or Del to access the boot menu during startup)
  3. Follow the Windows setup wizard — choose your language, accept the license, and select "Custom: Install Windows only"
  4. Select the drive and click Next. Windows will install and restart several times
  5. At the out-of-box experience (OOBE) screen, stop — let the buyer complete setup with their own Microsoft account

Tip: If the computer came with Windows originally, the license key is stored in the BIOS/UEFI firmware. Windows should activate automatically during installation without asking for a key.

Reinstalling macOS

After erasing in Disk Utility (via macOS Recovery), simply choose Reinstall macOS from the recovery utilities menu. The Mac will download and install the latest compatible version. Once it reaches the setup assistant, shut the Mac down — let the buyer go through setup themselves.

Recommended Tools

Not sure which tool to use? Here is a quick breakdown based on your situation:

Situation Recommended Tool Cost
Windows PC with SSD Windows Reset (built-in) Free
Windows PC with HDD DBAN Free
Mac (any modern) Erase All Content and Settings Free
Need an erasure certificate BitRaser Drive Eraser From $39
Wiping extra internal drives EaseUS BitWiper Free tier available
Quick wipe of external HDD KillDisk Free Free

For a full comparison of all the options, see our best data erasure software roundup.

Marketplace Safety Tips

Beyond wiping your data, keep these tips in mind when selling your computer:

  • Take photos of the serial number and specs before you wipe — you will need these for your listing
  • Remove any stickers that show asset tags, your name, or business information
  • Check for saved Wi-Fi passwords — these are erased during a full wipe, but worth noting if you used a partial reset
  • Include the charger and original accessories to increase the selling price
  • Meet in a public place if selling locally on Facebook Marketplace or Craigslist — many police stations have designated safe transaction zones
  • Ship with insurance and tracking if selling on eBay
  • Wipe immediately before selling — do not wipe the computer, then use it for another week before handing it over

Common Mistakes to Avoid

  • Thinking a format is the same as a wipe. A quick format only removes the file index — all the actual data remains on the disk and can be recovered in minutes. Our article on why formatting does not erase data explains this in detail.
  • Using the wrong method for SSDs. Running DBAN on an SSD is not effective and unnecessarily wears out the drive. SSDs need firmware-level commands, not multi-pass overwrites. Check our complete hard drive wiping guide for method recommendations by drive type.
  • Forgetting about secondary drives. Many desktops have two or more internal drives. The OS reset only wipes the system drive.
  • Not deauthorizing software first. You may lose access to paid software licenses if you wipe without deauthorizing.
  • Skipping verification. Always do at least a visual check after wiping. Errors happen — drives can have bad sectors that get skipped, or the process might fail silently.

Frequently Asked Questions

Is factory reset enough before selling a computer?

A factory reset removes your user profile and reinstalls the OS, but on a traditional hard drive, the underlying data often remains recoverable. For HDDs, use a dedicated wipe tool. For SSDs, a proper factory reset with the "clean data" option in Windows 11 or macOS Erase All Content and Settings is generally sufficient because these drives use hardware encryption.

Can someone recover my data after I wipe the drive?

If you performed a proper secure erase — a full overwrite for HDDs or a firmware-level sanitize command for SSDs — data recovery is extremely unlikely with any commercially available tools. A simple format or quick reset, on the other hand, leaves data fully recoverable.

Do I need to wipe an SSD differently than an HDD?

Yes. Traditional overwrite methods that work well on HDDs are unreliable on SSDs because of wear leveling and over-provisioning. SSDs should be erased using the manufacturer's Secure Erase or Sanitize command, or through the built-in OS reset features that trigger these commands automatically.

Should I just remove the hard drive instead of wiping it?

Removing the drive is the most foolproof approach, but it reduces resale value significantly. If you wipe using the methods in this guide, removal is unnecessary. If the drive contains highly sensitive data and you want extra peace of mind, remove it, keep it or destroy it, and sell the computer without a drive at a lower price.

How long does it take to wipe a hard drive before selling?

A full single-pass overwrite of a 1 TB HDD takes roughly 2 to 4 hours. SSD secure erase commands complete in seconds to minutes. Budget half a day for the entire process including backup, wiping, verification, and OS reinstallation.

Do I need to reinstall Windows after wiping?

Most buyers expect a working computer with a clean OS. Windows can be reinstalled from a USB drive using the free Media Creation Tool from Microsoft. A freshly installed OS adds value and gives the buyer a ready-to-use experience.

What about wiping a computer I am donating?

The same process applies whether you are selling, donating, or giving away your computer. Follow every step in this guide regardless of who receives it.

Will wiping deactivate my Windows license?

Windows digital licenses are tied to your hardware, not the data on the drive. Wiping and reinstalling on the same machine typically reactivates automatically. Consider unlinking your Microsoft account from the device beforehand if you want to transfer the license to a new computer instead.

Can I wipe my laptop without a USB boot drive?

Yes. Windows 10 and 11 offer "Reset This PC" without any external media. macOS Monterey and later on Apple Silicon or T2 Macs support "Erase All Content and Settings" from within the OS. These built-in options are the easiest approach for most people.

Is one overwrite pass really enough?

For any modern hard drive, a single full overwrite makes data unrecoverable with current technology. NIST 800-88 confirms this. The old advice about needing 3, 7, or 35 passes comes from research on outdated drive technology and has no practical relevance today.

The Bottom Line

Wiping your computer before selling it protects your personal data and takes less effort than most people expect. Back up your files, deauthorize your accounts, run a proper wipe using the right method for your drive type, verify the result, and reinstall a fresh OS. The whole process takes a few hours, and the privacy protection is well worth the time. Start with our complete guide to wiping a hard drive if you want more detail on any specific method.

Last updated: February 2026. We regularly review and update our guides to ensure accuracy.

Sources: