OpenCloud

What is OpenCloud?

OpenCloud is an open source platform for file management, sharing, and collaboration that you host on your own servers. Built in Go by the core engineering team behind ownCloud Infinite Scale (OCIS), it gives teams a private, GDPR-compliant place to store, sync, and share files — a self-hosted alternative to Dropbox, Google Drive, and SharePoint.

What is OpenCloud best for?

OpenCloud is best for organizations that mainly need file sync and share with document collaboration and care about data sovereignty and operational simplicity. It suits public-sector bodies, research and education institutions, and enterprises that want a lightweight, GDPR-compliant Dropbox replacement they fully control — without running a heavy application stack.

What can OpenCloud do?

• Sync and share files across web, desktop, and mobile clients, with delta synchronization that transfers only changed parts of a file.
• Collaborate on documents in real time through Collabora Online or OnlyOffice integrations (via the WOPI protocol).
• Run without a database — file and metadata storage lives entirely on the filesystem or S3, cutting operational complexity.
• Store on flexible backends, including POSIX filesystems (ext4, XFS, ZFS, CephFS, NFS) and native S3 buckets.
• Secure access with OpenID Connect authentication (embedded LibreGraph Connect or an external IdP like Keycloak), two-factor authentication, and granular access controls.
• Protect against ransomware through secure file versioning and Zero-Trust principles.
• Scale cleanly with a microservices architecture that separates storage, backend, and frontend, plus zero-downtime upgrades.

Where does OpenCloud fall short?

• Young app ecosystem. OpenCloud focuses tightly on files and document editing. It lacks the built-in groupware — calendar (CalDAV), contacts (CardDAV), mail, and video conferencing — that a broader platform like Nextcloud bundles, so it is a narrower tool by design.
• Less mature clients and community. The project launched in January 2025 as a fork of OCIS; mobile apps are functional but less polished, and its community (~5.9k GitHub stars) is far smaller than long-established alternatives, meaning fewer third-party apps and less community documentation.
• Office editing needs an extra service. Real-time document collaboration depends on running a separate Collabora or OnlyOffice server, which you deploy and maintain alongside OpenCloud.

Is OpenCloud free?

Yes — OpenCloud is free and open source under the Apache-2.0 license, and you can self-host it at no cost. The company behind it, Berlin-based Heinlein Group, offers paid subscriptions with enterprise support and SLAs, plus managed SaaS hosting through partners, but the software itself carries no license fee.

What does OpenCloud replace?

OpenCloud stands in for proprietary file storage and collaboration services. It is a self-hosted alternative to Dropbox, Google Drive, Microsoft SharePoint, and Box — keeping your files and documents on infrastructure you own rather than a vendor’s cloud.

FAQ

Is OpenCloud open source? Yes. OpenCloud is released under the Apache-2.0 license, a permissive open source license, and its source is on GitHub.

Can I self-host OpenCloud for free? Yes. The software is free to download and run yourself. Paid plans only add enterprise support, SLAs, or managed hosting — they are optional.

How is OpenCloud different from ownCloud and Nextcloud? OpenCloud is a Go-based fork of ownCloud Infinite Scale (OCIS), built by the same engineers. It is lighter to operate than PHP-based Nextcloud — no database, ~100 MB of RAM at rest — but far more focused: file sync, share, and document editing rather than a full groupware suite.

What do I need to run OpenCloud? A Linux server, a POSIX-compliant filesystem or S3 bucket, and no database. A minimal setup for up to 10 users runs on a single-core CPU and 512 MB of RAM (even a Raspberry Pi 3); around 1,000 users wants a dual-core CPU and 8 GB of RAM. Add a Collabora or OnlyOffice server for in-browser document editing.