When sharing sensitive files online, security should be your top priority. FileGrab’s end-to-end encryption feature ensures that your files are encrypted on your device before they’re uploaded to the cloud. This means that even FileGrab’s servers never see your unencrypted data.
In this tutorial, you’ll learn exactly how to use FileGrab’s end-to-end encryption to share files securely, understand how it works, and know when to use it.
What is End-to-End Encryption?
End-to-end encryption (E2E) means your files are encrypted on your device before they leave your browser. The encryption key is stored in the URL fragment (the part after the # symbol), which is never sent to FileGrab’s servers.
Here’s what makes FileGrab’s encryption secure:
- AES-256-GCM encryption - Military-grade encryption standard used by governments and security professionals
- Client-side only - All encryption happens in your browser using the Web Crypto API
- 4MB chunked encryption - Large files are encrypted in chunks for efficient processing
- HMAC-SHA256 signatures - Ensures file integrity and detects tampering
- Key in URL fragment - The decryption key never leaves your device or gets sent to servers
When Should You Use Encrypted Links?
Encrypted links are perfect for sharing:
- Financial documents (tax returns, bank statements, invoices)
- Medical records and healthcare information
- Legal documents (contracts, NDAs, sensitive agreements)
- Personal identification (passports, driver’s licenses, SSN documents)
- Confidential business files (trade secrets, proprietary data)
- Private photos and videos
If you’re sharing something you wouldn’t want anyone else to see, use an encrypted link.
Creating Your First Encrypted Link
Step 1: Upgrade to FileGrab Pro
End-to-end encryption is a premium feature available only to FileGrab Pro subscribers. If you’re on the free plan, you’ll need to upgrade first.
[SCREENSHOT: User menu dropdown showing “Upgrade to Pro” option]
- Click on your avatar in the top-right corner
- Select “Upgrade to Pro”
- Choose your billing plan (monthly or annual)
- Complete the checkout process
Step 2: Create a New Encrypted Link
Once you have FileGrab Pro, creating an encrypted link is simple:
[SCREENSHOT: User menu dropdown showing “New Encrypted Link” option highlighted]
- Click on your avatar in the top-right corner
- Select “New Encrypted Link”
- You’ll see a welcome modal explaining how encryption works
The first time you create an encrypted link, FileGrab shows you an informational modal explaining the encryption process and the importance of saving your URL.
[SCREENSHOT: First-time encryption modal with explanation and “Create Encrypted Link” button]
Step 3: Understanding the Encrypted Link URL
After creating your encrypted link, you’ll notice the URL has a special format:
https://filegrab.link/AGCUPZGT#8Kx9mP2qR5vN7yT3wB6jL4nS1gF0hDThe part after the # symbol is your encryption key. This is crucial to understand:
- Everything before the # is the link ID (sent to FileGrab’s servers)
- Everything after the # is the encryption key (never sent to servers)
- Without the key, the files cannot be decrypted
- You must share the complete URL (including the #key) with recipients
[SCREENSHOT: Link page showing shield badge next to link ID]
Notice the shield icon next to your link ID - this indicates the link is encrypted.
Step 4: Upload Your Files
Now you can upload files just like any other FileGrab link:
[SCREENSHOT: Encrypted link page with drag-and-drop area]
- Drag and drop files onto the page, or click to browse
- Files are automatically encrypted in your browser before upload
- Encrypted files are stored with a .enc extension on FileGrab’s servers
- You’ll see a lock icon instead of file type icons for encrypted files
The encryption process is completely transparent - you don’t need to do anything special. FileGrab handles all the encryption automatically.
Step 5: Share the Encrypted URL
This is the most important step: you must share the complete URL including the encryption key.
[SCREENSHOT: Copy URL button on encrypted link page]
Click the “Copy URL” button - FileGrab automatically copies the full URL with the encryption key included.
Critical warnings you’ll see:
- Navigation warning - If you try to leave the page (clicking “My Links” or closing the browser), FileGrab warns you to save the URL first
- Browser close warning - Your browser will show a standard “Are you sure you want to leave?” dialog
[SCREENSHOT: Navigation warning modal asking user to save the encrypted URL]
Once you close the browser or navigate away without saving the URL, the encryption key is lost forever. There is no recovery mechanism - this is by design for security.
How Recipients Access Encrypted Files
When someone receives your encrypted link:
With the Encryption Key
If they have the complete URL (including #key):
[SCREENSHOT: Encrypted link page from recipient’s view showing files with lock icons]
- They open the link in their browser
- Files are displayed with lock icons
- When they download a file, it’s automatically decrypted in their browser
- The decrypted file is saved to their device
Without the Encryption Key
If someone accesses the link without the #key fragment:
[SCREENSHOT: Missing encryption key modal blocking access]
- They see a modal explaining files cannot be decrypted
- The modal blocks all access to files
- “Go Back” button returns them to the previous page
- No file previews, downloads, or information is accessible
This is your security in action - without the key, the files are completely useless.
Encrypted Link Limitations
To maintain security, encrypted links have some intentional limitations:
No Thumbnails or Previews
Encrypted files cannot be previewed because FileGrab’s servers never see the unencrypted content. You’ll see lock icons instead of file thumbnails.
No Download All Feature
The “Download All” button is hidden on encrypted links because the server cannot create a ZIP file without decrypting the files first. Recipients must download files individually, which are decrypted on-the-fly in their browser.
No Individual File Sharing
Share buttons are hidden for individual files on encrypted links. This prevents someone from sharing a single file without the encryption key, which would make it inaccessible.
Collaboration Not Recommended
While you can enable collaboration on encrypted links, it’s not recommended. When others upload to your encrypted link, they’ll use the same encryption key, which reduces the security benefit of E2E encryption.
Best Practices for Encrypted Links
1. Save the URL Immediately
As soon as you create an encrypted link, save the complete URL in a secure location:
- Password manager (1Password, Bitwarden, LastPass)
- Encrypted notes app (Standard Notes, Notion with encryption)
- Secure messaging app (Signal, WhatsApp)
Never save it in plain text files or unencrypted email drafts.
2. Share Through Secure Channels
Send the encrypted URL through secure channels:
- Best: Encrypted messaging apps (Signal, WhatsApp, Telegram)
- Good: Email with the key sent separately through another channel
- Avoid: Public forums, social media, SMS
For extra security, send the link ID and encryption key through different channels.
3. Use Short Expiry Times
Even though Pro users can create “forever” links, consider setting shorter expiry times for encrypted links with sensitive data. Once the recipient has downloaded the files, the link can expire.
4. Verify the Recipient
Before sharing an encrypted link with sensitive data, verify you’re sending it to the right person:
- Double-check email addresses and phone numbers
- Use video calls to verbally confirm receipt
- Ask recipients to confirm they received and opened the link
5. Delete When Done
After your recipient has successfully downloaded the files, delete the link from your FileGrab account. This removes the encrypted files from storage and invalidates the link permanently.
Troubleshooting Common Issues
”Files cannot be decrypted” Error
This means the encryption key is missing from the URL. Check that you shared the complete URL including the #key part.
Files Download but Won’t Open
This can happen if:
- The recipient’s browser doesn’t support the Web Crypto API (very old browsers)
- There was network corruption during download
- The file was tampered with (HMAC verification failed)
Have the recipient try downloading again in a modern browser (Chrome, Firefox, Safari, or Edge).
Encryption Feels Slow for Large Files
FileGrab encrypts files in 4MB chunks, which is efficient for most files. However, encrypting very large files (1GB+) will take longer because the encryption happens in your browser. This is normal and ensures security.
How Secure Is FileGrab’s Encryption Really?
FileGrab uses the same encryption standards as:
- Proton Drive - Encrypted cloud storage service
- Tresorit - Enterprise encrypted file sharing
- Signal - Encrypted messaging app
- Bitwarden - Password manager
The encryption implementation:
- Uses the browser’s native Web Crypto API (not custom JavaScript crypto)
- Generates cryptographically secure random keys
- Applies proper key derivation and HMAC signatures
- Never sends the encryption key to servers
- Encrypts files before they leave your device
Unless someone has your encryption key, your files are mathematically impossible to decrypt without breaking AES-256 encryption (which would require billions of years with current computing power).
Encryption vs Password Protection
FileGrab offers both encryption and password protection. Here’s when to use each:
Use encryption when:
- Files contain highly sensitive data
- You need mathematical security guarantees
- You’re sharing with a trusted recipient who can handle the URL properly
Use password protection when:
- You need simpler recipient access
- You want to share a shorter URL and send the password separately
- The recipient might not be technical
You can use both together for maximum security - encrypt the link and add a password. This provides defense in depth.
Start Sharing Securely Today
FileGrab’s end-to-end encryption gives you bank-level security for file sharing without requiring any technical expertise. Your files are encrypted automatically, and recipients decrypt them seamlessly in their browser.
Ready to share files with complete privacy? Upgrade to FileGrab Pro and create your first encrypted link in seconds.
FileGrab Pro includes:
- End-to-end encryption with AES-256-GCM
- 10GB storage and 2GB file uploads
- Forever links with no expiry
- Password protection and collaborative links
- No ads, ever
Try FileGrab Pro today and experience truly secure file sharing.