How to Encrypt Files and Folders on Any Operating System

Why File Encryption Matters

Encryption transforms your readable files into scrambled data that can only be unlocked with the correct key or password. Without encryption, anyone who gains access to your hard drive, whether through theft, a lost laptop, or unauthorized access, can read every document, view every photo, and access every saved password on the device.

Consider what is stored on your computer right now: tax documents, personal photos, financial records, medical information, work files, and saved passwords. A single unencrypted stolen laptop can lead to identity theft, financial fraud, professional embarrassment, or worse. File encryption ensures that even if physical security fails, your data remains protected.

Encryption is also critical when sharing sensitive files. Sending an unencrypted document via email means it could be intercepted, stored on mail servers, or accessed by unauthorized parties. Encrypting files before sharing them adds a layer of protection that persists regardless of how the file is transmitted.

Built-In Encryption on Each Operating System

Windows: BitLocker

BitLocker is Microsoft's full-disk encryption tool available on Windows Pro, Enterprise, and Education editions. It encrypts your entire drive so that all files are protected automatically. To enable BitLocker, open the Control Panel, navigate to System and Security, and select BitLocker Drive Encryption. Choose the drive you want to encrypt and follow the setup wizard.

BitLocker uses AES-128 or AES-256 encryption and integrates with your computer's TPM chip for seamless authentication. You can unlock your drive with a PIN, a USB key, or your Windows password. Always save your recovery key in a safe location separate from your computer, as losing it means losing access to your encrypted data permanently.

For Windows Home users who lack BitLocker, the Device Encryption feature provides basic protection on supported hardware. Check Settings, then Privacy and Security, then Device Encryption to see if your system supports it.

macOS: FileVault

Apple's FileVault 2 provides full-disk encryption for Mac users using XTS-AES-128 encryption. Enable it through System Settings, then Privacy and Security, then FileVault. The process is straightforward and encryption happens in the background while you continue using your Mac.

FileVault ties encryption to your user account password, so choosing a strong password is essential. Apple offers to store your recovery key in iCloud or you can record it manually. For maximum security, store the recovery key yourself rather than in iCloud, and keep it in a physically secure location.

Linux: LUKS

Linux Unified Key Setup is the standard for Linux disk encryption. Most Linux distributions offer LUKS encryption as an option during installation. If you did not enable it during setup, you can encrypt individual partitions or create encrypted containers using the cryptsetup command.

For file-level encryption on Linux, GPG provides a powerful command-line option. You can encrypt individual files with symmetric encryption using the command gpg -c filename, which will prompt you for a passphrase and create an encrypted version of the file.

Third-Party Encryption Tools

VeraCrypt

VeraCrypt is a free, open-source encryption tool that works on Windows, macOS, and Linux. It creates encrypted containers, which are virtual drives stored as files that you mount when needed and dismount when not in use. VeraCrypt also supports full-disk encryption and hidden volumes for plausible deniability.

To create an encrypted container with VeraCrypt, launch the application, click Create Volume, and follow the wizard. Choose a strong password and select AES encryption for the best balance of security and performance. When you need to access your encrypted files, mount the container through VeraCrypt and it appears as a regular drive on your system.

7-Zip Encryption

For encrypting individual files or folders, 7-Zip offers a practical solution. This free, open-source archiving tool supports AES-256 encryption. Right-click any file or folder, select 7-Zip, then Add to Archive, and enter an encryption password. The resulting archive is portable and can be decrypted on any system with 7-Zip or a compatible tool.

Browser-Based Encryption

For quick text encryption without installing software, browser-based tools offer convenience with privacy. Our text encryption tool lets you encrypt sensitive text directly in your browser. The encryption happens entirely on your device, meaning your unencrypted data never leaves your computer or travels over the network.

Browser-based encryption is ideal for quickly encrypting a message, a password, or a small piece of sensitive information before sharing it via email or messaging. For larger files and long-term storage, use the operating system or third-party tools described above.

Best Practices for File Encryption

Choose Strong Passwords

Your encryption is only as strong as the password protecting it. Use our password generator to create a long, random password for your encrypted volumes and files. Avoid reusing passwords across different encrypted containers.

Back Up Your Recovery Keys

Losing your encryption password or recovery key means permanent data loss. Store recovery keys in a separate physical location from the encrypted device. Consider printing them and storing them in a safe, or using a password manager that is itself backed up.

Encrypt Before Uploading

Before uploading sensitive files to cloud storage or sharing them via email, encrypt them locally first. This provides protection even if the cloud service is breached or the email is intercepted. Use our PDF tools to work with PDF documents locally, and encrypt sensitive documents before storing them anywhere outside your control.

Verify Your Encryption Works

After setting up encryption, test the recovery process. Lock yourself out intentionally and use your recovery key to regain access. It is far better to discover a problem during a test than during an actual emergency when you desperately need your data.

File encryption is one of the most effective privacy measures available, and modern tools have made it accessible to everyone regardless of technical skill level.