Proton Drive

Proton Drive is a secure cloud storage service developed by Proton AG, extending the company’s zero-access encryption philosophy to file storage and sharing. Every file uploaded to Proton Drive is encrypted on your device before transmission, ensuring that your documents, photos, and data remain completely private—even from Proton employees.

Unlike mainstream cloud storage providers that can access your files to scan content, serve targeted advertising, or comply with government requests, Proton Drive’s architecture makes this technically impossible. Files are encrypted using AES-256 and your personal encryption keys, which never leave your device. This means that a data breach, rogue employee, or court order cannot expose your files because Proton simply cannot decrypt them.

Proton Drive is headquartered in Geneva, Switzerland, with all data stored on servers exclusively in Switzerland, Germany, and Norway. This provides protection under Swiss privacy law—among the strongest in the world—and places your data outside the reach of US surveillance programs. The service is ISO 27001 certified, SOC 2 Type II attested, and fully compliant with GDPR, HIPAA, and CCPA regulations.

The service offers native apps for Windows, macOS, iOS, Android, and web, with automatic synchronization across all devices. Features include secure file sharing with password protection and expiration dates, Proton Docs for real-time collaborative document editing, Proton Sheets for encrypted spreadsheets, and easy migration from other cloud storage providers.

Key Features

• Zero-Access Encryption: Files encrypted before upload, unreadable even to Proton
• Proton Docs: Collaborative document editing with end-to-end encryption
• Proton Sheets: Encrypted spreadsheets for budgets and data analysis
• Secure Sharing: Password-protected links with customizable expiration dates
• Cross-Platform Apps: Native apps for Windows, macOS, iOS, Android, and web
• Automatic Sync: Keep files synchronized across all your devices
• Version History: Recover previous versions of your files

Privacy Highlights

Proton Drive implements client-side encryption using AES-256 for file contents and OpenPGP for metadata. Encryption keys are derived from your account password and stored encrypted on Proton’s servers—only you can decrypt them. This zero-knowledge architecture ensures that Proton cannot access your files under any circumstances.

All infrastructure is wholly owned by Proton and located in Switzerland, Germany, and Norway. The company publishes regular transparency reports documenting legal requests received, and their technical architecture means they have nothing useful to provide even when legally compelled.

Privacy Breakdown

Data Residency (Score: 100)

Pros:

• All data stored in Switzerland, Germany, and Norway exclusively
• Swiss Federal Act on Data Protection (FADP) jurisdiction
• Outside Five Eyes, Nine Eyes, and Fourteen Eyes alliances
• Proton owns all server infrastructure

Cons:

• None identified

Confidence: High — verified through Proton documentation and transparency reports.

Open Source (Score: 90)

Pros:

• All client applications fully open source on GitHub
• Independent security audits conducted
• Cryptographic libraries publicly auditable
• Community can verify encryption implementation

Cons:

• Server-side code not open source

Confidence: High — code available at github.com/ProtonMail.

Privacy Policy (Score: 88)

Pros:

• Clear explanation of minimal data collection
• No data monetization or advertising
• User retains full ownership of content
• Transparent about what metadata is accessible

Cons:

• File sizes and folder structure technically visible to Proton

Confidence: High — policy reviewed January 2026.

Trackers (Score: 95)

Pros:

• No third-party analytics trackers
• No advertising networks
• Privacy-respecting telemetry only (can be disabled)

Cons:

• Basic crash reporting for app stability

Confidence: High — verified through app analysis.

Terms of Service (Score: 65)

Pros:

• User owns all uploaded content
• No broad licensing claims on user data
• Clear data portability rights

Cons:

• Standard SaaS limitations of liability
• Arbitration provisions included
• Account termination policies standard but not exceptional

Confidence: Medium — ToS reviewed January 2026.