Works with the calendars you already use
Sign in to Google Calendar, Outlook, iCloud, or Fastmail. Other calendars connect with a link you paste in, or over the CalDAV standard they already support.
Features
Keeper.sh copies events from one calendar into another and combines everything you connect into a single feed. Works with Google Calendar, Outlook, iCloud, Fastmail, and more.
One calendar link with everything in it
Every calendar you connect also lands in a single link. Subscribe to it from any calendar app and your whole week shows up in one place.
Share that you are busy, not what you are doing
The link hides titles, descriptions, and locations by default. Every event reads “Busy”, so you can hand it to a colleague without handing over your schedule. On Pro you pick which details it keeps and what the stand-in title says.
Connections go one way
A connection copies events from one calendar into another. If you want both calendars to match, connect them in both directions.
Copies that stay right
Move an event and the copy moves. Delete it and the copy goes too. Your other calendar gets corrected instead of collecting duplicates.
Open-source, and yours to run
Keeper.sh is open-source under AGPL-3.0, with Docker images ready to deploy. Run it yourself and every account on it gets the Pro feature set, with no plan limits.
How your calendars stay in step
You set a connection up once. After that, Keeper.sh keeps the copies right.
1
Connect a calendar, then say where it copies to
Connecting takes a sign-in or a pasted link. You then point that calendar at the one you want its events to land in.
2
Choose what each calendar shows
You set this per calendar. A work calendar can carry the title, description, and location while a shared one shows a plain block. On Pro you can also filter out events you would rather not copy at all.
3
Keeper.sh takes it from there
Your calendars are checked every minute on both plans. Google and Outlook only report what changed, so checking stays quick even on a packed calendar. A change reaches your other calendars within 30 minutes on Free, and within a minute on Pro.
Calendars connected by a link are read in full each time.
For developers
Skip this part unless you want to drive Keeper.sh from your own code or from an assistant.
REST API
Keeper.sh exposes a REST API under /api/v1, authenticated with a bearer token you create under Settings → API Tokens. It covers accounts, calendars, events, invites, and the calendar link.
The free plan allows 25 API calls per day. Pro is uncapped.
MCP server
An assistant can read and write your calendars through Keeper.sh’s MCP server. You approve it once on a consent screen in your browser, and it signs in with OAuth 2.1 rather than a password.
- Read: list_calendars, list_accounts, get_events, get_event, get_event_count, get_pending_invites, get_ical_feed
- Write: create_event, update_event, delete_event, rsvp_event
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