Best open-source alternatives to Microsoft PowerPoint

reveal.js is an open source HTML presentation framework designed for creating slide decks in the browser. It is aimed at anyone who wants to build visually polished presentations without relying on traditional desktop presentation software. The project emphasizes a feature-rich presentation experience, including nested slide navigation, Markdown-based authoring, auto-animated transitions, PDF export, speaker notes, LaTeX math rendering, and syntax-highlighted code. The README also points users to a live demo, installation instructions, documentation, and a paid visual editor service from Slides.com.

CryptPad is a self-hostable collaboration suite focused on privacy and end-to-end encryption. It lets people work together on shared content in real time while keeping the stored data encrypted, so the service operators cannot read the content if the server is compromised. The project is open source and is intended for users and organizations that want collaborative editing without giving the hosting provider access to the underlying documents. The platform includes several collaborative applications such as documents, spreadsheets, presentations, forms, kanban boards, code, rich text, and whiteboards. It supports deployment for development and production, with Docker-based setup available and separate installation guidance for administrators. The README also points users to documentation, release notes, translation infrastructure, community forums, and security guidance for using instances safely.

GenOffice is an open-source office suite that combines document editing with AI assistance. It is positioned as an alternative to Microsoft Office for macOS, Windows, and Linux, and supports working with native Word, Excel, PowerPoint, PDF, Markdown, and HTML files while preserving real file formats. The project is aimed at users who want local, editable office workflows with AI help layered directly into the document, spreadsheet, presentation, and PDF experience. The README emphasizes that files are opened, edited, saved, and converted on-device, while AI calls can use the user’s chosen provider or a signed-in Genspark account. It also includes a command-line interface and agent integrations, suggesting it is designed not only for interactive office work but also for automation and developer-driven workflows.

ONLYOFFICE Docs is a self-hosted online office suite intended for teams and organizations that need collaborative document editing inside their own infrastructure or within third-party platforms. It provides editors for text documents, spreadsheets, presentations, forms, PDFs, and diagrams, with compatibility for Office Open XML formats. The project is designed to integrate with products such as ONLYOFFICE DocSpace, ONLYOFFICE Workspace, and external sync-and-share systems like Nextcloud, Moodle, ownCloud, Seafile, and Odoo. It emphasizes real-time co-editing, review and change tracking, version history, plugins, and a range of editor features such as spell-checking, accessibility options, and dark mode. The README also describes multiple editions, including a free community edition and paid enterprise/developer offerings.

Collabora Online Development Edition (CODE) is a powerful LibreOffice-based online office that supports all major document, spreadsheet and presentation file formats, which you can integrate in your own infrastructure.

Create multimedia presentations in a quick and easy way. (documentation in French).