If you’ve been looking for a secure, privacy-respecting, and feature-rich alternative to Microsoft Office 365, there’s never been a better time to try Collabora Online.
With the latest Collabora Online 25.04 release, your browser is a high-performance, enterprise-ready online office suite – faster, more accessible, and more capable than ever before. Whether you’re collaborating in real-time, managing complex spreadsheets, or delivering sleek presentations, this is open-source office work without compromise.
Here’s why Collabora Online continues to be the top choice for organisations, governments, and privacy-minded users around the world.
If you’ve been looking for a secure, open-source, and self-hosted Microsoft Office 365 alternative, there’s never been a better time to try Collabora Online.
Updated on 08/08/2025.
1. Full Control & Digital Sovereignty in Your Office Suite
Collabora Online can be self-hosted or integrated into your own cloud platform (Nextcloud, Drupal, WordPress, Moodle, Seafile…), keeping all documents under your control. Unlike Microsoft 365, there’s no forced cloud storage or vendor lock-in – you decide where your data lives and who can access it.
And now with the new Rootless Containers deployment and Server Signature Hiding in 25.04, your infrastructure is more secure against targeted attacks and easier to manage without compromising isolation.
2. Unmatched Format Support & Interoperability with Microsoft Office
Collabora Online works beautifully with Microsoft (DOCX, XLSX, PPTX…) and OpenDocument (ODF) formats, keeping your documents looking sharp.
The 25.04 release builds even further on our solid compatibility interop foundations with:
- PDF 2.0 support for more secure, modern PDF workflows
- Font embedding in PPTX to preserve your presentation styles everywhere
So rest assured, you’ll still have access to that legacy Microsoft Works file you have lying around. Got an unusual client who likes everything sent to them in .docm? Not a problem. You can even import FlatXML spreadsheets with ease. With Collabora Online, you’ll have all the interoperability you need for your modern, or indeed legacy working environment.
3. Familiar Interface Online, Offline & On the Go
Whether you’re on Mac, Windows, or Linux, working from a desktop, mobile device, or your favourite modern browser, Collabora Online gives you freedom of choice. Unlike many alternatives, our browser-based and desktop applications share the same core codebase – so the slideshow you edited on your laptop will behave exactly the same when you present it online.
You’ll also feel instantly at home with Collabora Online’s familiar, user-friendly interface. There’s no steep learning curve and no need for costly retraining – you can get straight to work.
And with the new Collabora Online 25.04 release, that smooth experience is faster than ever:
- Viewport-Based Preloading for lightning-fast rendering of long documents.
- Smoother Editing with up to 60fps responsiveness.
- Faster XLSX handling for massive spreadsheets.
The result? A responsive, reliable editing experience that feels like a native desktop app – wherever and however you choose to work.
4. Powerful Collaboration Tools for Teams
The clue’s in the name! Collabora Online allows you to collaborate, co-edit, review and track changes, add comments, and share your documents securely. Furthermore, Collabora Online gives you a whole range of security and permission settings, enforced server side, to ensure your data and the content of your documents, is always protected.
The 25.04 update now includes:
- Improved Comments with @mentions, parent-child threading, and quick shortcuts.
- Per-User Change Tracking for granular control over revisions.
UserCanOnlyComment mode — perfect for controlled review processes. - Reinstate Changes to track when deletions are rejected and restored.
Whether you’re in legal, education, or enterprise, enjoy clear communications and the clean version history you need.
5. No More Vendor Lock-In — Freedom from Proprietary Office Suites
Tired of creeping subscription costs or unexpected changes to the tools you rely on? With Collabora Online, you stay in control. Our open-source, standards-compliant office suite works with your infrastructure – not against it.
You’re free to host it yourself, run it in the cloud with one of our 200+ partners, or adopt a hybrid approach. And if your needs change, you can switch providers or move fully on-premise without disruption.
6. Accessibility & Global Language Support in Your Office Tools
Accessibility has taken a leap forward in 25.04 with 100+ improvements, making Collabora Online easier to navigate with keyboards, screen readers, and assistive devices. Complex writing systems are handled more accurately also thanks to:
- Better quotation mark rendering in CJK/Western text mixes.
- Precise indentation using typographic units.
- No more clipped diacritics in languages like Arabic.
These updates ensure your documents are usable and beautiful, in any language.
Conclusion - The Open-Source Advantage
Choosing a Microsoft Office alternative isn’t just about matching features – it’s about finding a solution that respects your data, adapts to your workflows, and gives you freedom. Collabora Online delivers all of that.
It combines enterprise-grade performance with the transparency and flexibility of open source. You can run it on your own servers, integrate it with your existing cloud, and know your documents stay under your control. It works with the file formats you already use, while embracing open standards for long-term accessibility.
With real-time collaboration, robust editing tools across documents, spreadsheets, and presentations, and a development team committed to continuous improvement, Collabora Online isn’t a compromise – it’s a step forward.
Try Collabora Online today and see how powerful your browser can be.
2 Responses
I’d like to know more about Collabora Online’s file format support, LibreOffice has broad support, although I am not sure to what extent. Does Collabora Online support the same file formats?
https://en.wikipedia.org/wiki/LibreOffice#Supported_file_formats
https://www.collaboraoffice.com/collabora-online/
Hi Rob, yes Collabora Online supports the same file formats as LibreOffice.