Proton
how to encrypt files

When you encrypt files on your computer, it’s like storing them in a vault: Only someone with the correct key can access them. That’s useful if you’re concerned about hackers stealing your most sensitive documents or companies scanning your data for advertising.

In this how-to guide, we’ll show you the easiest ways to encrypt your files on Windows, Mac, iOS, and Android. We’ll also explain how you can encrypt your files on the cloud, or create new files that are encrypted by default, and then access them on any device.

What is encryption and why use it?

Modern computing is possible because of encryption. It’s the reason you can buy things online and share photos privately with friends. But much of the encryption used online isn’t as secure as you might think. When you share a picture using Google Photos, the company can see it. When you upload something to Dropbox, the company can see it. And if the government requests your data or uses mass surveillance to monitor you, your files may not be private.

Luckily there are other types of encryption that can prevent even the most data-hungry companies like Google and Facebook from accessing your files. That’s the kind of encryption we’re talking about in this article.

We won’t go into the technical details of end-to-end encryption or symmetric encryption(new window) here (you can learn more about them by following those links). But the encryption methods described below are designed to prevent any third parties from accessing your files. 

There are many times when encrypted file storage is useful, including:

  • Backing up sensitive documents, such as tax filings or identity documents
  • Storing workplace documents or data covered by privacy regulations, such as the GDPR or HIPAA
  • Keeping your most important documents safe in case your device is hacked or lost
  • Sharing files over the internet or storing them in the cloud
  • Reducing the amount of personal information you share with companies like Google, Facebook, Dropbox, and Microsoft
You can securely encrypt your files with Proton Drive

How to encrypt files with Windows

Encrypting individual files in Windows is simple. It’s just a matter of right-clicking on the file or folder you want to encrypt and following the instructions below. (Note that this feature is not available for Windows 10 Home.)

  1. Right-click or press and hold the file or folder you want to encrypt. Select Properties.
  2. Click the Advanced… button and check the box next to Encrypt contents to secure data
  3. Select OK to close the Advanced Attributes window and then select Apply.
  4. Click OK.

Learn how to encrypt your entire hard drive in Windows

How to encrypt files with Mac

There’s no single method to encrypt individual files on your Mac because different file types have different steps. In fact, the easiest way to encrypt a file on your Mac is to move it to a folder and encrypt the folder.

Here’s how:

  1. Move the file or files you want to encrypt to a new or existing folder. Make sure you want to encrypt all the files in this folder.
  2. Next, go to FinderApplicationsUtilities.
  3. Open Disk Utility.
  4. In the Disk Utility application, select File from the top menu and select New ImageImage from Folder.
  5. Select the folder you want to encrypt and click on Choose.
  6. In the window that pops up, choose the kind of encryption you want to use. (Both 128-bit and 256-bit encryption are secure options.) Then enter a password. Do not lose this password. If you do not have your password, it will be impossible to recover your files. Click on Choose when you’re finished.
  7. Next to Image Format, select Read/Write and click on Save.

To access the folder again, double-click it and enter your password.

How to encrypt files on an Android

Android devices don’t come with built-in encryption capabilities for individual files, and most third-party encryption apps for Android are not user friendly. The easiest way to encrypt files on your Android device is with encrypted cloud storage.

Here’s how to secure your files with end-to-end encryption using Proton Drive:

  1. Install Proton Drive for Android(new window).
  2. Open the Proton Drive app and log in using your Proton Drive username and password. If you don’t have a Proton Account, you can sign up for free.
  3. Tap Files at the bottom or tap the hamburger menu () and select My files.
  4. Tap (+) at the top right and select Upload a file from the dropdown menu.
  5. Select the photos or files you want to upload and tap Open.

Note: This process creates an encrypted copy of your file in your Proton Drive account but does not encrypt the file stored on your device. You’ll need to delete the local file after ensuring the copy is properly stored in Proton Drive.

How to encrypt files on an iPhone

Apple iPhones also don’t have a built-in way to encrypt individual files. It’s very easy to encrypt your entire device, though. Just go to Settings and select Face ID & Passcode. From there you can enable Face ID and a passcode for your device. However, this option doesn’t necessarily encrypt all your files if you back up your data to iCloud or share data with apps such as Google Maps or social media.

The most secure way to encrypt files on your iPhone is with encrypted cloud storage. Here’s how to use Proton Drive in iOS:

  1. Download Proton Drive for iOS(new window).
  2. Open the Proton Drive app and log in using your Proton Drive username and password. If you don’t have a Proton Account, you can sign up for free.
  3. Tap Files at the bottom or tap the hamburger menu (☰) and select My files.
  4. Tap (+) at the top right and select Upload a photo or Import file from the dropdown menu.
  5. Tap files to upload them or select photos to upload and tap Add.

Note: This process creates an encrypted copy of your file in your Proton Drive account but does not encrypt the file stored on your device. You will need to delete the local file after ensuring the copy is properly stored in Proton Drive.

Benefits of encrypted cloud storage

For Android and iOS, there aren’t many great options for encrypting individual files locally on your device. That’s why we recommend using the Proton Drive apps for encrypted cloud storage on mobile. There are benefits for using cloud encryption, and we recommend it for Windows and Mac as well. You can download the Proton Drive apps for Windows and Mac devices and seamlessly sync and access files from your desktop.

With Proton Drive, your files are encrypted on your device before they’re sent to the cloud — so not even Proton can access them. From there, you’ll be able to access your encrypted files from any device by logging in to your Proton Account on the web or through our apps.

How to create encrypted documents

Docs in Proton Drive also allows you to create and collaboratively edit documents that are encrypted from the moment you begin. Available on the web, Docs ensures that any sensitive information you add to a document can never be accessed by anyone, including hackers or even Proton.

Unlike Google Docs, our document editor allows you to create drafts privately. Whatever you write, including your file name, will be safe from data breaches and online surveillance, and can never be fed into AI models.

Here’s how to access Docs in Proton Drive:

  1. Go to Proton Drive(new window).
  2. Click New and select New document.

Learn more about Proton Drive security

Apart from end-to-end encryption, Proton Drive has the added benefit of secure file sharing.

Share large files for free

If you’ve ever tried and failed to attach a large video or multiple photos to an email, you know the hassle of file size limits. With encrypted cloud storage, you can first upload large files to your account and then share them with your recipient from there. Proton Drive lets you securely send large files for free, with no limit on the size of the file you upload.

Secure link sharing

Most storage services allow you to share files by generating a link. This is also true for Proton Drive. Once you’ve uploaded a file, you can share it with anyone using secure link sharing. The files remain end-to-end encrypted, and anyone with the link can download the file.

Password-protected files

If you’re sending a file with a sharing link but want to add an extra layer of protection, you can use password-protected file sharing. Just create a sharing link, turn on password protection, and set a password. In Proton Drive, you can also set the link to expire after a period of time.

FAQ

How do I encrypt a file with a password?

In Windows, right-click the file you want to encrypt and select Properties. Select the Advanced… button and check the Encrypt contents box to secure your file. In Mac, you’ll need to open the Disk Utility application and go to FileNew ImageImage from Folder and select the folder you want to encrypt. Then select your preferred encryption and set a password.

What is the most secure way to encrypt a file?

Using AES encryption on your device or an end-to-end encrypted cloud storage service, like Proton Drive, will ensure that only you can decrypt your files with your password.

How do I encrypt a PDF file?

How to encrypt a PDF file in Acrobat:
– Open the PDF in Acrobat and go to ToolsProtectMore OptionsEncrypt with Password.
– Under Document Open, check the box next to Require a password to open the document.
– Under Options, select the version of Acrobat that will be required to open the document. Acrobat X is recommended.
– Select what you want to be encrypted: the contents or the contents and metadata.
– Click OK.
Learn more about encrypting PDFs

What does it mean to encrypt a file?

File encryption is the process of converting readable data into unreadable ciphertext. It can only be restored to readable data using a private key.

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