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Best Free Alternatives to SpiderOak One Backup
Stop paying $6/mo (150GB) - $29/mo (5TB). Discover professional-grade tools that won't break your budget.
Category: Zero-Knowledge Backup & SyncVerified for 2025
Top Recommended Replacements
Proton Drive
FREEBest Modern Privacy Ecosystem
Why we like it
100% open-source and Swiss-based; mandatory end-to-end encryption; includes 'Proton Sheets' and 'Docs' for secure collaboration; 2FA support.
Keep in mind
Syncing can be slower than SpiderOak due to heavy encryption; does not support Linux desktop natively yet (limited to web/CLI).
Tresorit
FREEBest for Enterprise-Grade Security
Why we like it
Exceptional admin controls and audit trails; zero-knowledge encryption with patented cryptographic technology; supports e-signatures and secure file requests.
Keep in mind
One of the most expensive options on the market; no 'unlimited' storage tier; free plan is very small (3GB).
MEGA
FREEBest for Free Storage Capacity
Why we like it
Generous 20GB free tier; zero-knowledge encryption is standard for all users; includes encrypted chat and video calling; very fast transfer speeds.
Keep in mind
Transfer quotas apply to the free tier; the company's past history makes some corporate users cautious.
Sync.com
FREEBest for Simple Secure Backup
Why we like it
Canadian-based with strict privacy laws; zero-knowledge by default; unlimited file versioning and recovery on professional plans; zero file-size limits.
Keep in mind
Lacks 'block-level' sync (re-uploads entire files when changed); no native Linux client; basic user interface.
IDrive
FREEBest Value for Large Backups
Why we like it
Supports unlimited devices; provides zero-knowledge 'private key' encryption option; includes disk imaging and physical drive shipping for fast restores.
Keep in mind
Zero-knowledge key must be set at startup and cannot be reset; interface is functional but dated compared to Proton.
Filen.io
FREEBest Emerging Open-Source Choice
Why we like it
German-based with 100% zero-knowledge encryption; very affordable lifetime plans; open-source desktop and mobile clients; modern UI.
Keep in mind
Smaller team; currently lacks the advanced 'Point-in-Time' full-system restore found in SpiderOak One.
Icedrive
FREEBest Modern UI & Virtual Drive
Why we like it
Mounts cloud storage like a physical drive (Windows); uses Twofish encryption; beautiful minimalist interface; generous free tier.
Keep in mind
Zero-knowledge encryption is restricted to the paid 'Encrypted' folder; lacks real-time document collaboration.
Cryptomator
FREEBest for 'DIY' Cloud Encryption
Why we like it
Not a storage provider, but a tool that encrypts files *before* they reach Google Drive/Dropbox; 100% free for desktop; privacy-first.
Keep in mind
Requires managing two different apps (Cryptomator + your cloud provider); no 'recovery key' if you lose your password.
Internxt
FREEBest for Decentralized Security
Why we like it
Uses blockchain-inspired technology to fragment and encrypt files across nodes; open-source and highly transparent; EU-based.
Keep in mind
Decentralized sync can lead to inconsistent speeds; very small free tier (1GB); less mature feature set.
Kopia
FREEBest for Advanced Technical Users
Why we like it
Cross-platform backup engine with built-in deduplication and encryption; zero-knowledge; works with any S3/WebDAV backend (like Hetzner or Backblaze B2).
Keep in mind
No built-in storage; requires high technical knowledge to configure and maintain backups.
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