replacing Microsoft 365
Open Source Microsoft 365 Alternatives
Office suite and cloud services — Microsoft 365 pricing: $6-$22/user/month. Below: 2 free,
self-hostable open source projects that cover the same ground, ranked by real GitHub adoption.
There are 2 open source Microsoft 365 alternatives tracked on this registry, against Microsoft 365 pricing of $6-$22/user/month. The most-adopted is Nextcloud with 36,828 GitHub stars under AGPL-3.0, written in PHP. Together the set has 41,201 stars across 2 languages and 2 licences. All 2 are free to self-host with no licence fee, and 2 of 2 received a commit in the last 90 days. 2 head-to-head Microsoft 365 comparisons are available.
M365 requires annual commitment for the best pricing. Files live on OneDrive/SharePoint. No perpetual license option for businesses.
Our top 2 Microsoft 365 alternatives
Nextcloud is a self-hosted cloud collaboration platform built in PHP, licensed under AGPL-3.0. It enables organizations and individuals to store, synchronize, and share files, contacts, calendars, and other data on infrastructure they control, replacing reliance on third-party cloud services. The project lives in the open-source cloud software ecosystem and serves as a decentralized alternative to proprietary suites like Dropbox, Google Workspace, and Microsoft 365.
AGPL-3.0 · PHP · Microsoft 365 vs Nextcloud →
LibreOffice is an integrated office suite written in C++ and distributed under GPL-3.0. It lives in the open-source productivity and office suite ecosystem, and it positions itself as an open alternative to Microsoft 365. The Document Foundation backs the project as a community of enterprises, developers, and volunteers.
GPL-3.0 · C++ · Microsoft 365 vs LibreOffice →
last updated nightly · ranking method: github stars, live-tracked
Frequently asked questions
What is the best open source alternative to Microsoft 365?
Nextcloud is the most-starred open source alternative to Microsoft 365 in this registry, with 36,828 GitHub stars. 2 alternatives are compared here in total.
Are there free alternatives to Microsoft 365?
Yes. Every project listed on this page is open source and free to self-host — there is no licence fee. Some projects also sell a managed hosted version, but the self-hosted path costs nothing.
What should I look at when replacing Microsoft 365?
Compare licence terms, community size (stars), primary language and release activity. A fast-moving project with a compatible licence and an active maintainer base matters more than raw star count when you are committing to a migration.