CryptPad

CryptPad is an open-source office suite for online collaboration. The server cannot read your documents, all encryption happens on your device.

Included applications:

• Rich Text documents
• Spreadsheets
• Code/Markdown editor
• Kanban boards
• Slides
• Whiteboard
• Polls

Features:

• Zero-knowledge encryption
• Real-time collaboration with author colors
• Chat and comment systems built-in
• Self-hosting available
• Official instance hosted by XWiki-SAS