CalendarPipe

CalendarPipe syncs events between Google Calendar, Microsoft Outlook, and Apple Calendar through "pipes" — rules that decide which events cross between your calendars and what they look like when they arrive. You can build a rule visually, describe it in plain English, or write it as TypeScript that runs in a sandbox with no network access.

That covers cases plain sync tools don't: mirroring personal commitments onto a work calendar as opaque "Busy" blocks, stripping titles and guest lists before events cross a boundary, or syncing only events that match a tag.

It also supports invitation-based delivery, which sends events as standard iCalendar invitations to a calendar it has no OAuth access to — useful when an employer blocks third-party calendar apps, since nothing needs installing or approving on the work account.

A REST API and MCP server let AI agents own and manage their own calendars, with invitations delivered to any inbox.

The free plan is permanent and covers 2 calendar connections and 1 sync rule at a 15-minute sync interval. Pro is $4/month or $40/year for unlimited connections and rules at 5-minute intervals, AI rule generation, and API access.