Create an option to make the Open Document Format (ODF) the default file format

[GerryT11]

As pointed out in [1], the support of the Open Document Format (ODF) cannot be set as default file format. It would be great if such an option exists. This (and full ODF comptability) is also needed, e.g., for fulfilling the Germany’s Sovereign Digital Stack [2]. Similar efforts exist in other countries.

[1, on OnlyOffice 22.03.2026] https://community.onlyoffice.com/t/make-the-open-document-format-odf-a-first-level-citizen-in-onlyoffice/18930
[2] https://blog.documentfoundation.org/blog/2026/03/19/germanys-sovereign-digital-stack-mandates-odf/

[jorge2000x]

I mean, is it possible to integrate ODF into OnlyOffice without having to rewrite a large part of the code?

[ifrh]

I mean, is it possible to integrate ODF into OnlyOffice without having to rewrite a large part of the code?

Well , there exists :

https://github.com/Euro-Office/core/tree/main/OdfFile

[randolf]

Supporting ODF is an important part of supporting the open source movement. The "Save" and "Save as..." dialogues should include a note above the file type drop-down that encourages people to choose ODF (and be an underlined hyperlink that changes the drop-down selection to ODF). This will gradually increase awareness among end-users about open standards.

[InfoLibre]

Ideally, I'd like to open MSOffice files, edit them as MSOffice files and save them as MSOffice files AND I'd like to open OpenDocument files, edit them as OpenDocument files and save them as OpenDocument files, while still retaining the option to convert them. OnlyOffice/Euro-Office should no longer convert OpenDocument files to MSOffice format before saving them, without my consent.

[GlassedSilver]

Ideally, I'd like to open MSOffice files, edit them as MSOffice files and save them as MSOffice files AND I'd like to open OpenDocument files, edit them as OpenDocument files and save them as OpenDocument files, while still retaining the option to convert them. OnlyOffice/Euro-Office should no longer convert OpenDocument files to MSOffice format before saving them, without my consent.

Good point, but a separate issue I think. What you describe is actually a bug fix, because for the love of God, whoever made this the behavior in OnlyOffice is a maniac.

[InfoLibre]

emberfiend said it wasn't a separate issue: Euro-Office/DocumentServer#37

[GlassedSilver]

I think the issue you created there got misinterpreted.

If you hadn't linked me to it with the context of this thread I would have thought it's the same issue as this one, but at the end of the day all you want is for files to not be destructively converted silently.

Very different ball game.

[Laquinh]

I believe ODF should be the default file format by default, and there should exist an option to make OOXML default just in case somebody needs it. Not the other way around.

[InfoLibre]

Documents are degraded when you convert them between OpenOffice and MSOffice formats. It's better to open a file in its original format without converting it and to keep it in this format when you register it. If the user wants to convert it, it's his choice. And it's better to let user choose in which format he wants to create a new document. Then, no need anymore to have a default file format and everybody will be happy.
But perhaps it's impossible to do this without having two different software, LibreOffice+OnlyOffice, into Euro-Office?

[GlassedSilver]

I believe ODF should be the default file format by default, and there should exist an option to make OOXML default just in case somebody needs it. Not the other way around.

I agree with this strongly.

ODF is way more predictable and standardized, since it defines precisely how things are rendered and stored, whereas OOXML has a defined way to store data, but rendering is a bit of a proprietary mess on MS' side if I recall correctly.

At the end of the day we come up with three main goals to further compatibility and supporting open and proper standards and predictability:

1. ODF should be the standard whenever new files get created.
2. Users should be able to disagree and set their own standard.
3. When opening files of the major types, they shouldn't be converted - especially silently - to any other document type family.
   So OOXML stays OOXML, ODF stays ODF, OG MS Office .DOC, .PPT and .XLS should stay OG MS Office if it can be helped.
4. When users make use of functions that exceed the scope of compatible features of that given doc type ideally they should be warned before their usage so they are aware of any possible needs to convert once they intend to save their edits to disk. This I assume is also highly relevant for compliance reasons, since governments and institutions are starting to mandate usage of specific formats and exchanging files with partners may still limit users to stay within a certain type of document family.

[GlassedSilver]

Documents are degraded when you convert them between OpenOffice and MSOffice formats. It's better to open a file in its original format without converting it and to keep it in this format when you register it. If the user wants to convert it, it's his choice. And it's better to let user choose in which format he wants to create a new document. Then, no need anymore to have a default file format and everybody will be happy. But perhaps it's impossible to do this without having two different software, LibreOffice+OnlyOffice, into Euro-Office?

There will always be a need to have a default file format, the scope of setting one doesn't necessitate that docs get converted/degraded.

Having a default format makes sure you don't need to select a given standard (possibly erroneously) every single time you create a document.

Like I said, make ODF the default, let users decide for themselves, don't silently change doc type family in the background and warn users when they are about to apply changes incompatible with their doc type family the document is currently stored/drafted as. That way you should in theory catch all major gotchas.