2 Free & Open-Source Microsoft Office Alternatives
Microsoft 365 is billed per user, recurring, whether or not everyone on a team needs the full suite every month. LibreOffice and ONLYOFFICE both read and write standard Office file formats, so documents move between them and Microsoft Office without much friction for typical business use.
The best Microsoft Office alternatives
LibreOffice
Our top pickOpen sourceDesktop appA free, open-source office suite with Word/Excel/PowerPoint compatibility.
LibreOffice covers writing, spreadsheets, and presentations with broad compatibility for .docx, .xlsx, and .pptx files — the long-standing default free office suite, actively maintained with regular releases.
- Writer, Calc, and Impress (Word/Excel/PowerPoint equivalents)
- Reads and writes Microsoft Office file formats
- No account or subscription of any kind
- Free, open-source, desktop app for Windows/Mac/Linux
ONLYOFFICE
Open sourceDesktop appAn office suite with a closer visual match to Microsoft's own interface.
ONLYOFFICE's ribbon-style interface looks and behaves closer to Microsoft Office than LibreOffice's, which shortens the adjustment period for teams switching from Word/Excel/PowerPoint — available as a desktop app or self-hosted for team document collaboration.
- Interface closely modeled on Microsoft Office's ribbon UI
- Strong .docx/.xlsx/.pptx format fidelity
- Real-time collaborative editing when self-hosted
- Free desktop app; self-hosted server edition also open-source
Licensing and pricing models change over time — confirm current terms on each project's own site before making a procurement or compliance decision.
Frequently asked questions
Will documents look right when opened in Microsoft Office after editing?
For typical business documents, yes — both tools have solid format compatibility. Very complex documents with advanced macros or unusual formatting are where small discrepancies are most likely to show up.
Which is closer to Microsoft Office's interface — LibreOffice or ONLYOFFICE?
ONLYOFFICE, deliberately — its ribbon-style layout was designed to feel immediately familiar to Office users. LibreOffice has its own distinct interface that takes a bit more adjustment.
Can teams collaborate on documents in real time like Microsoft 365?
ONLYOFFICE supports real-time collaborative editing when self-hosted on its Document Server. LibreOffice is primarily a desktop app without built-in real-time co-editing.
More free alternatives
Not sure which way to go?
A free Growth Audit can help you weigh self-hosting against the tool you already pay for.