How to Permanently Delete Files So They Can’t Be Recovered (Windows, Mac & Linux Guide)

When you delete a file normally, your computer doesn’t actually remove the data. It simply marks that storage space as “available.” The original data remains on your drive until new data overwrites it.

To permanently delete files so they cannot be recovered, you must overwrite the data. The correct method depends on your device and whether you use a HDD (Hard Disk Drive) or SSD (Solid State Drive).

1. Windows – Securely Deleting Individual Files

If you need to permanently delete sensitive documents, use a file-shredding tool that overwrites the file multiple times.

Best Free Tools

• BleachBit – Open-source and easy to use.
• Eraser – Allows right-click secure deletion.

After installation, simply right-click the file and select Securely Delete.

Wipe Deleted Free Space (Built-in Windows Method)

If you already deleted files normally, you can wipe the free space using Command Prompt:

1. Open Command Prompt as Administrator.
2. Type: cipher /w:C: (Replace C: with your drive letter).

This overwrites all free space so previously deleted files cannot be recovered.

Advanced Tool: Microsoft Sysinternals SDelete

For advanced users, SDelete is a powerful command-line tool from Microsoft for secure file deletion and free-space wiping.

2. Mac – Modern Built-in Security

Modern Macs (Apple Silicon or T2 security chip) use full-disk encryption by default.

Standard Deletion

When you delete a file and empty the Trash, the encryption key protecting that file is destroyed. Without the key, the remaining data becomes unreadable.

For External Drives (HDD Only)

1. Open Disk Utility.
2. Select the external drive.
3. Click Erase.
4. Choose Security Options (available only for mechanical HDDs).

You can select how many overwrite passes to perform.

3. Linux – Using the “shred” Command

Linux includes a built-in tool called shred for secure file deletion.

To overwrite and delete a file:

shred -uvn 3 filename

• -u removes the file after shredding
• -v shows progress
• -n 3 performs three overwrite passes

⚠️ Important: SSD vs HDD Differences

Traditional HDD (Mechanical Drive)

Overwriting works reliably because data is stored in fixed physical locations.

Modern SSD & NVMe Drives

SSDs use a technology called wear leveling. This means overwriting a single file may not target the exact physical memory cells where the original data was stored.

Therefore, file shredding is less reliable on SSDs.

The Most Secure Method for SSDs

Use the manufacturer’s official utility to perform an ATA Secure Erase. This securely resets all memory cells at once.

• Samsung SSD → Samsung Magician
• Western Digital → WD Dashboard
• Crucial → Crucial Storage Executive

Quick Summary

Final Advice

If your device contains extremely sensitive information, the safest option is:

• Enable full-disk encryption from day one.
• Use manufacturer Secure Erase tools for SSDs.
• Physically destroy drives if required for high-security environments.

Need step-by-step help for your specific system (Windows 11, macOS Sonoma, Ubuntu, etc.)? Tell me your setup and I’ll guide you precisely.