Filen is a cloud storage service with end-to-end, zero-knowledge encryption — meaning your files are encrypted on your device before they ever leave it, and Filen’s servers never see your decryption keys. Unlike traditional cloud services (Google Drive, Dropbox, OneDrive) where the provider can read your files, Filen’s architecture mathematically prevents them from doing so. This review covers what Filen offers, how its encryption works, how to set it up, and how it compares to alternatives.
What Is Zero-Knowledge Encryption?
In zero-knowledge cloud storage:
- Your files are encrypted locally using a key derived from your password (using PBKDF2 with SHA512)
- The encrypted ciphertext is uploaded to Filen’s servers
- Filen never receives your password or encryption keys
- Only you — with your password — can decrypt the files
The consequence: if Filen is hacked, attackers get encrypted data that’s useless without your key. Filen employees cannot access your files. However, if you forget your password and lose your recovery key, your data is permanently inaccessible — Filen genuinely cannot recover it.
Filen Plans and Pricing
| Plan | Storage | Price |
|---|---|---|
| Free | 10 GB | Free forever |
| 100 GB | 100 GB | ~€2.99/month |
| 200 GB | 200 GB | ~€4.99/month |
| Starter | 200 GB | ~€29.99/year |
| 1 TB | 1 TB | ~€9.99/month |
| Lifetime plans | 100 GB–10 TB | One-time payment |
Filen periodically offers lifetime storage plans at significant discounts — worth checking filen.io for current promotions. The lifetime 200 GB plan has historically been available for around €30.
Installing Filen
Desktop (Windows, macOS, Linux)
Download the Filen desktop app from https://filen.io/downloads. The app provides:
- Cloud drive sync — sync specific local folders to Filen
- Virtual drive mount — mount your Filen storage as a virtual disk (F: or similar) via WebDAV
- Background sync — like Dropbox, automatic syncing of designated folders
Mobile (iOS, Android)
Available on both app stores. Full feature set including automatic photo backup, offline file access, and the same E2EE throughout.
Setting Up Your Account
- Sign up at filen.io — provide an email and password
- Save your Recovery Key immediately — shown during signup; this is the only way to regain access if you lose your password. Store it in a password manager or printed offline copy
- Download and install the desktop app
- Log in — the app creates a local encryption key from your password
Configuring Sync
In the Filen desktop app:
- Click Sync in the left sidebar
- Click Add sync location
- Choose a local folder (e.g.,
C:\Users\Pat\Documents) - Choose a remote Filen folder (e.g.,
/Documents) - Select sync mode:
- Two-way: Changes sync in both directions
- Local to cloud: Upload-only (local is master)
- Cloud to local: Download-only (like a remote backup)
Click Save — sync begins immediately.
Using the Virtual Drive
The virtual drive feature mounts your Filen storage as a local disk. On Windows, it appears as F: (or your chosen letter) in File Explorer:
- In Filen desktop → Virtual Drive
- Enable the drive and assign a drive letter
- Open File Explorer — your Filen files appear as local files
You can open, edit, and save directly to the virtual drive. Files are transparently encrypted/decrypted by the Filen app. This is useful for working with files without a full local sync — only the file you access is downloaded on demand.
Filen Drive (Web Interface)
Access your files at https://drive.filen.io. The web interface provides file management, sharing, and viewing. Note that using the web client requires your encryption keys to be handled by JavaScript — purists may prefer the desktop app for higher security assurance.
Sharing Files and Folders
Filen supports secure sharing:
- Share with another Filen user — end-to-end encrypted using their public key
- Public link — generates a shareable URL with optional password protection and expiry date
- Send — temporarily share files with non-Filen users
Public links encrypt the file with a random key that’s embedded in the URL fragment (after #). The server never receives this key, maintaining zero-knowledge even for shared files.
Filen Notes
Filen also includes an encrypted notes application — similar to Standard Notes. Notes are E2EE and sync across devices. A solid all-in-one option if you want both cloud storage and encrypted notes in one service.
How It Compares to Alternatives
| Service | Storage | Price | E2EE | Open Source |
|---|---|---|---|---|
| Filen | 10 GB free | From €2.99/mo | Yes | Yes (client) |
| Proton Drive | 1 GB free | From €3.99/mo | Yes | Yes (client) |
| Tresorit | None free | From €12/mo | Yes | No |
| Cryptomator + Any Cloud | Varies | Free+cloud cost | Yes | Yes |
| Google Drive | 15 GB free | From $2.99/mo | No | No |
Filen stands out for its generous free tier, affordable paid plans, lifetime plan availability, and open-source clients. Proton Drive is the closest alternative with comparable security and a more established company behind it.
Limitations to Know
- Password reset = data loss: No backdoor means a lost password and lost recovery key means permanently lost data
- Collaboration features: Filen isn’t designed for real-time collaboration like Google Docs
- Performance: Virtual drive streaming adds latency vs. local files
- Company: Filen is a smaller company than Proton — lower risk tolerance users may prefer Proton’s larger backing
For individuals and small teams wanting straightforward private cloud storage without the complexity of self-hosting, Filen is one of the best-value options available in 2026.