Keeper.sh — Open-Source Calendar Syncing for Google, Outlook & iCloud

# Keeper.sh > Open-source calendar event syncing. Synchronize events between your personal, work, business and school calendars. Keeper.sh is an open-source (AGPL-3.0) calendar synchronization service that keeps time slots aligned across multiple calendar providers. It uses a pull-compare-push architecture to sync events between Google Calendar, Outlook, FastMail, iCloud, CalDAV, and iCal feeds. ## Key Features - Universal calendar sync across Google Calendar, Outlook, Apple Calendar, FastMail, CalDAV, and iCal feeds - Privacy-first: only busy/free time blocks are shared by default, with granular controls for titles, descriptions, and locations - Aggregated iCal feed generation for sharing availability externally - MCP (Model Context Protocol) server for AI agent calendar access via OAuth 2.1 - Self-hostable with Docker Compose (standalone, services-only, or individual containers) - Free tier (30-minute sync, 2 accounts) and Pro tier ($5/month, 1-minute sync, unlimited) ## Links - [Homepage](https://keeper.sh) - [Blog](https://keeper.sh/blog) - [Privacy Policy](https://keeper.sh/privacy) - [Terms & Conditions](https://keeper.sh/terms) - [GitHub Repository](https://github.com/ridafkih/keeper.sh) - [Full LLM Context](https://keeper.sh/llms-full.txt)