Microsoft 365 is still the suite the world speaks — especially Excel. LibreOffice is the full free alternative. ONLYOFFICE is free too and often handles Word/Excel files more cleanly. Pay for 365 when compatibility is the job.
Microsoft 365
Why it won →“Excel, Word, PowerPoint, Outlook — the formats everyone expects. Worth it when co-workers and clients live here.”
Alternatives
Runner-up
LibreOffice
A complete free office suite that works offline.
A complete free suite that works offline with no seat fee. Great for most documents; heavy Excel models still want Microsoft.
Also good
ONLYOFFICE Desktop Editors
Free desktop editors that play nicely with Word and Excel files.
Free desktop editors that round-trip .docx and .xlsx especially well. Strong Microsoft-format alternative.