← Knowledge Base

Microsoft Office Alternatives: LibreOffice, OnlyOffice, and the Sovereignty Question

By Tom Langston ·

  • Software
  • Open Source
  • Office
  • Sovereignty
  • Productivity

TL;DR

You do not have to pay for, or be locked into, Microsoft Office. There are genuinely good free alternatives, and the best of them open your existing Word, Excel, and PowerPoint files with very little fuss. The standouts: LibreOffice (the mature, do-everything open suite) and OnlyOffice (the best at Microsoft-format compatibility). Avoid the now-stagnant Apache OpenOffice. And keep an eye on Euro-Office, a brand-new European, sovereignty-focused suite built on OnlyOffice. Underneath it all sits a bigger issue: Microsoft’s document format has quietly become the world’s default, and that is a problem worth caring about.

Now for the more technical explanation

LibreOffice: the mature all-rounder

LibreOffice is the big, free, open-source office suite: a word processor (Writer), spreadsheet (Calc), presentations (Impress), and more. It is genuinely capable, actively developed, and used by governments and organisations moving off Microsoft. Its native format is the open OpenDocument standard, but it opens and saves Microsoft files too. If you want one free suite that does everything and is here to stay, this is the safe pick.

OnlyOffice: the Microsoft-compatibility champion

If your world revolves around Word and Excel files, OnlyOffice is the one to try. Its whole design goal is faithful compatibility with Microsoft’s formats, and it shows: the vast majority of .docx, .xlsx, and .pptx files open cleanly, without the janky, shifted formatting you sometimes get elsewhere. Tables, styles, and layouts mostly just look right. Its interface will also feel familiar to anyone coming from modern Office.

It is not perfect. In real use, the odd small embedded image, say a social icon like a Facebook or LinkedIn logo in an email signature or a document footer, can show up as an empty box rather than the picture. Minor, and usually cosmetic, but worth knowing if your documents lean on lots of tiny embedded graphics. For everyday documents, though, the fidelity is excellent.

Apache OpenOffice: skip it now

Apache OpenOffice carries the name of the original open-source suite, but it has effectively stagnated, development slowed to a crawl years ago and it lags badly on features and fixes. The lineage is worth getting right: LibreOffice was forked from OpenOffice.org in 2010, a year before Oracle handed that codebase to Apache, so the two are siblings rather than parent and child, and LibreOffice long ago surpassed it. If you have OpenOffice out of habit, move to LibreOffice; there is no good reason to start with OpenOffice today.

Euro-Office: the new European sovereignty play

The newest and most interesting entrant is Euro-Office, launched in June 2026. It is a European, open-source, sovereignty-driven suite, explicitly built to reduce the EU’s dependence on Microsoft Office, and it is built on OnlyOffice (so it inherits that strong Microsoft-format compatibility). It launched web-first, integrated with Nextcloud, which is why a proper standalone desktop version is the thing to watch for. As a statement of intent, that a bloc would build its own office suite to escape one vendor, it is a genuinely exciting step, and it puts the sovereignty argument front and centre.

There is even a healthy debate around it: some in the LibreOffice camp argue that by chasing perfect Microsoft-format compatibility, Euro-Office reinforces Microsoft’s format as the standard rather than pushing the open one. Which brings us to the real issue.

The formats: ODF vs OOXML (the part that actually matters)

Underneath the apps are two document standards:

So when you ask whether Microsoft’s format is “officially” or “unofficially” the standard, the uncomfortable answer is both: it is technically an official standard and the overwhelming de facto default, achieved through market dominance rather than open consensus.

Why the dominance is a problem

Microsoft’s document format has been the world’s default for decades, and that is not healthy. When a single company’s format becomes what everyone must read, write, and exchange, you get:

The healthiest long-term answer is the open standard (ODF) owned by no one. The pragmatic short-term reality is that you still have to exchange .docx with everyone else, which is exactly why the compatibility of tools like OnlyOffice matters so much.

And yes, Microsoft Office in the browser is an option

Microsoft also offers free web versions of Word, Excel, and PowerPoint (Office for the web). They are handy and genuinely free for basic use, but they come with limitations: a reduced feature set compared with the desktop apps, a hard requirement to be online and signed into a Microsoft account, and formatting that can still come out janky or shifted on complex documents. Useful in a pinch, not a full replacement.

What is the best free alternative to Microsoft Office?

The short version

You are not stuck with Microsoft Office. LibreOffice is the mature free all-rounder, OnlyOffice is the compatibility champion that opens your .docx files cleanly (bar the odd tiny embedded image), Apache OpenOffice is a dead end, and Euro-Office is an exciting new sovereign, OnlyOffice-based option to watch. Beneath the app choice is the real story: the open ODF standard belongs to everyone, while Microsoft’s format has dominated for too long, and quietly becoming the world’s default, official or not, is exactly what makes it a problem.

Written by Tom Langston, IT Infrastructure and Cybersecurity.