# 5 Best Open Source Alternatives for Microsoft 365

Canonical: https://caniforkit.com/microsoft-365
Last updated: 2026-11-07

Looking for the best open source alternative for Microsoft 365? Compare 5 verified free and open source alternatives to Microsoft 365 (CryptPad, Papra, ONLYOFFICE Docs) with license details, self-hosting requirements, and practical trade-offs.

## Microsoft 365 Overview & Subscription Cost
- **Product**: Microsoft 365
- **Category**: [notes & knowledge](https://caniforkit.com/category/notes-knowledge)
- **Paid Subscription Price**: $10/month per seat
- **1-Seat Annualized Cost**: $120/year
- **5-Person Team Annualized Cost**: $600/year
- **10-Person Team Annualized Cost**: $1,200/year
- **Can I Vibe-Code / Rebuild It Myself?**: NO (use a free alternative, save the tokens)
- **Rebuild Verdict**: Instead of paying recurring SaaS fees for Microsoft 365 or rebuilding it from scratch, deploy one of the 5 battle-tested open-source alternatives like CryptPad.

## Verified Free & Open Source Alternatives

| Alternative | Type | License | Runs On | GitHub Stars | Head-to-Head |
| --- | --- | --- | --- | --- | --- |
| [CryptPad](https://caniforkit.com/fork/cryptpad) | Open Source | AGPL-3.0+ | Self-host | ★ 8.1k | [Compare vs Microsoft 365](https://caniforkit.com/vs/microsoft-365-vs-cryptpad) |
| [Papra](https://caniforkit.com/fork/papra) | Open Source | Open Source | Self-host | ★ 5.7k | [Compare vs Microsoft 365](https://caniforkit.com/vs/microsoft-365-vs-papra) |
| [ONLYOFFICE Docs](https://caniforkit.com/fork/onlyoffice-docs) | Open Source | Open Source | Self-host | ★ 7.1k | [Compare vs Microsoft 365](https://caniforkit.com/vs/microsoft-365-vs-onlyoffice-docs) |
| [LibreOffice](https://caniforkit.com/fork/libreoffice) | Open Source | Open Source | Local | ★ 4.6k | [Compare vs Microsoft 365](https://caniforkit.com/vs/microsoft-365-vs-libreoffice) |
| [Collabora Online](https://caniforkit.com/fork/collabora-online) | Open Source | Open Source | Self-host | ★ 3.4k | [Compare vs Microsoft 365](https://caniforkit.com/vs/microsoft-365-vs-collabora-online) |

## In-Depth Alternative Profiles

### CryptPad
- **Fork Page**: [CryptPad Profile](https://caniforkit.com/fork/cryptpad)
- **Head-to-Head Comparison**: [Microsoft 365 vs CryptPad](https://caniforkit.com/vs/microsoft-365-vs-cryptpad)
- **Official Website**: https://cryptpad.org/
- **Source Code Repository**: https://github.com/cryptpad/cryptpad
- **License**: AGPL-3.0+
- **Runs On**: Self-host
- **GitHub Stars**: 8.1k
- **Maintenance Activity**: nov 2026
- **Supported Platforms**: web, self-hosted, they host it
- **Summary**: Open-source collaboration suite offering encrypted document editing, file sharing, and team workspaces with complete privacy protection.
- **The Catch vs Microsoft 365**: CryptPad provides a stronger encrypted drive but its whiteboard is markedly less delightful and capable for drawing, libraries, and diagram composition than Excalidraw+.
- **Installation**: Use a public CryptPad instance, or self-host the Node.js service behind a reverse proxy
- **Setup**: Public hosting is immediate; self-hosting requires two domains or subdomains, HTTPS, strict security headers, Node.js configuration, persistent storage, and careful upgrades/backups
- **Data Storage**: Documents are encrypted in the browser before upload; the server stores encrypted document files, blobs, and account pin metadata on its filesystem and cannot read document content

### Papra
- **Fork Page**: [Papra Profile](https://caniforkit.com/fork/papra)
- **Head-to-Head Comparison**: [Microsoft 365 vs Papra](https://caniforkit.com/vs/microsoft-365-vs-papra)
- **Official Website**: https://papra.app
- **Source Code Repository**: https://github.com/papra-hq/papra
- **License**: Open Source
- **Runs On**: Self-host
- **GitHub Stars**: 5.7k
- **Maintenance Activity**: nov 2026
- **Supported Platforms**: web, self-hosted, docker to self-host
- **Summary**: A document management platform that helps you archive, organize, and search files with email ingestion, tagging capabilities, and powerful search functionality.
- **The Catch vs Microsoft 365**: Requires self-hosting setup, updates, and server maintenance compared to managed Microsoft 365.
- **Installation**: Clone https://github.com/papra-hq/papra or deploy with Docker Compose
- **Setup**: Deploy via Docker or binary release from GitHub and configure environment variables.
- **Data Storage**: All application data and configuration live on your own server or local database.

### ONLYOFFICE Docs
- **Fork Page**: [ONLYOFFICE Docs Profile](https://caniforkit.com/fork/onlyoffice-docs)
- **Head-to-Head Comparison**: [Microsoft 365 vs ONLYOFFICE Docs](https://caniforkit.com/vs/microsoft-365-vs-onlyoffice-docs)
- **Official Website**: https://www.onlyoffice.com/office-suite.aspx
- **Source Code Repository**: https://github.com/onlyoffice/documentserver
- **License**: Open Source
- **Runs On**: Self-host
- **GitHub Stars**: 7.1k
- **Maintenance Activity**: nov 2026
- **Supported Platforms**: web, self-hosted, docker to self-host
- **Summary**: Open-source online editor for documents, spreadsheets, presentations, and PDFs. Features real-time collaboration, AI integration, and accessibility tools.
- **The Catch vs Microsoft 365**: Requires self-hosting setup, updates, and server maintenance compared to managed Microsoft 365.
- **Installation**: Clone https://github.com/onlyoffice/documentserver or deploy with Docker Compose
- **Setup**: Deploy via Docker or binary release from GitHub and configure environment variables.
- **Data Storage**: All application data and configuration live on your own server or local database.

### LibreOffice
- **Fork Page**: [LibreOffice Profile](https://caniforkit.com/fork/libreoffice)
- **Head-to-Head Comparison**: [Microsoft 365 vs LibreOffice](https://caniforkit.com/vs/microsoft-365-vs-libreoffice)
- **Official Website**: https://www.libreoffice.org
- **Source Code Repository**: https://github.com/libreoffice/core
- **License**: Open Source
- **Runs On**: Local
- **GitHub Stars**: 4.6k
- **Maintenance Activity**: nov 2026
- **Supported Platforms**: desktop, cross-platform, one-click install
- **Summary**: Complete free office suite compatible with Microsoft formats (.doc, .docx, .xls, .xlsx, .ppt, .pptx). Open source alternative with regular updates.
- **The Catch vs Microsoft 365**: Community-driven open source project without dedicated enterprise SLAs.
- **Installation**: Clone https://github.com/libreoffice/core or deploy with Docker Compose
- **Setup**: Download the native package or installer for your operating system.
- **Data Storage**: All application data lives locally on your own machine.

### Collabora Online
- **Fork Page**: [Collabora Online Profile](https://caniforkit.com/fork/collabora-online)
- **Head-to-Head Comparison**: [Microsoft 365 vs Collabora Online](https://caniforkit.com/vs/microsoft-365-vs-collabora-online)
- **Official Website**: https://www.collaboraonline.com
- **Source Code Repository**: https://github.com/collaboraonline/online
- **License**: Open Source
- **Runs On**: Self-host
- **GitHub Stars**: 3.4k
- **Maintenance Activity**: nov 2026
- **Supported Platforms**: web, self-hosted, docker to self-host
- **Summary**: Powerful online document editor with Microsoft Office compatibility. Integrate into your infrastructure or use trusted hosting partners for secure team collaboration.
- **The Catch vs Microsoft 365**: Requires self-hosting setup, updates, and server maintenance compared to managed Microsoft 365.
- **Installation**: Clone https://github.com/collaboraonline/online or deploy with Docker Compose
- **Setup**: Deploy via Docker or binary release from GitHub and configure environment variables.
- **Data Storage**: All application data and configuration live on your own server or local database.

## Frequently Asked Questions

### What is the best free alternative to Microsoft 365?
The top free alternative to Microsoft 365 is CryptPad (open source, AGPL-3.0+). Open-source collaboration suite offering encrypted document editing, file sharing, and team workspaces with complete privacy protection. Other popular Microsoft 365 replacements include Papra, ONLYOFFICE Docs, LibreOffice.

### How much does switching from Microsoft 365 to a free alternative save?
Microsoft 365 starts at $10/month per seat ($120/year). Switching a 5-person team to a free alternative like CryptPad saves $600 per year in software subscription fees.

### What is the catch when switching away from Microsoft 365?
While CryptPad replaces core Microsoft 365 features without subscription fees, the real-world trade-off is: CryptPad provides a stronger encrypted drive but its whiteboard is markedly less delightful and capable for drawing, libraries, and diagram composition than Excalidraw+.

## Related

- [notes & knowledge Software Category Hub](https://caniforkit.com/category/notes-knowledge)
- [All Paid SaaS Alternatives Index](https://caniforkit.com/alternatives)
- [Self-Hosted Software Directory](https://caniforkit.com/self-hosted)
- [Homepage](https://caniforkit.com)