Your files, sealed and synced.
CattStack is encrypted cloud storage built for teams that treat their data like it matters. Every file is sealed on your device before it ever leaves it.
No card required · Works on macOS, Windows, Linux, iOS & Android
Trusted by product, legal, and research teams at
Storage that earns its keep
Sync, share, and recover files without handing your keys to anyone — not even us.
Zero-knowledge encryption
Files are sealed with AES-256 on your device. Your passphrase never reaches our servers, so a breach exposes nothing.
90-day version history
Every save is a checkpoint. Roll a document — or an entire folder — back to any point in the last 90 days.
Granular sharing
Share a single file or a whole vault with expiring links, view-only mode, and per-member permissions.
Search inside files
Full-text search across PDFs, docs, and images — indexed locally so your content stays private.
EU data residency
Data lives in ISO 27001 facilities in Reykjavík and Helsinki. You choose the region; we never move it.
Selective sync
Keep 2 TB in the cloud and only what you need on disk. Pin folders offline with a click.
Up and running in three steps
No migration project, no IT ticket. Most teams are synced before their coffee cools.
Create a vault
Pick a name and a passphrase. CattStack derives your keys locally — we never see them.
Drop your files
Drag a folder in or point the desktop app at an existing one. Everything seals as it uploads.
Invite your team
Add members by email and set roles. They get exactly the access you grant, nothing more.
See your whole library at a glance
Preview, restore, and share from one fast window — on desktop, mobile, or the web.
Start with 15 GB, free forever
Spin up your first vault in under a minute. Upgrade only when your team outgrows it.
Create your vault