Free calendar sync
Keeper.sh is a calendar sync service that copies events between Google Calendar, Outlook, iCloud, Fastmail and any CalDAV server, so every calendar shows you as busy at the same times. It is free for 2 calendar accounts and 3 connections, and Pro is $5 a month for unlimited calendars.
Start for freeWhat the Free plan includes
The Free plan costs $0, needs no card and is not a trial. It connects the same calendar services as Pro.
Calendar accounts
2An account is one signed-in calendar service, however many calendars it holds. A Google account with five calendars is 1 account.
Connections
3A connection is one calendar sending events into one other calendar. Each connection runs one way, so two-way sync is two connections.
Shareable calendar links
1One link covering the calendars you choose, for subscribing from any calendar app. Every event in it reads "Busy".
Update speed
Every 30 minutesOn Free, changes land every 30 minutes, on every calendar service. A connection you add or remove syncs straight away.
Calendar services
Google Calendar, Outlook, iCloud, Fastmail, CalDAVGoogle and Outlook connect by signing in on their own permission screens. iCloud connects with an app-specific password and Fastmail with an app password. A CalDAV server connects with its address and your sign-in details. A pasted .ics link is read-only: events copy out of it and nothing writes back.
What a copy shows
A busy blockEach copy is a busy block named after the source calendar. The title, description and location are hidden, and guest lists are never copied.
Copy range
1 month back, 2 years aheadEvents inside that range are copied and kept matched to their originals: move, shorten or delete the original and the copy follows.
API and AI assistant access
25 calls a dayThe REST API and the MCP server for AI assistants share one allowance of 25 calls a day.
What the Free plan is enough for
A two-way pair uses 2 accounts and 2 connections, which fits the Free plan with one connection spare.
Work and personal calendars, both ways
2 accounts, 2 connectionsA work Outlook mailbox and a personal Google account, each sending its events to the other. Colleagues see your personal commitments as busy blocks, and your personal calendar shows your meetings.
A booking page that checks one calendar
2 accounts, 1 connectionA personal iCloud calendar sending its events to the Google or Outlook calendar that Calendly or another booking tool checks, so those hours stop being offered.
Three calendars across two accounts
2 accounts, 3 connectionsA personal calendar and a family calendar in one account both sending to a work calendar in the other, and the work calendar sending back to the personal one.
One link showing when you are busy
2 accounts, 1 linkA shareable calendar link covering every calendar in both accounts, for a partner, a colleague or a client to subscribe to. A link uses no connections.
How to set up free calendar sync
1. Create an account
Sign up with an email address and a password. No card is asked for.
2. Connect two calendar accounts
Sign in to Google or Outlook on their own permission screens. iCloud connects with an app-specific password and Fastmail with an app password.
3. Choose the directions and start
Keeper.sh offers a switch for each direction between the two calendars. Leave both on for two-way sync and choose Start syncing.
When you need Pro
Pro is $5 a month, or $45 a year, for one person. It is the only paid plan. Compare the plans.
A third calendar account
Work, personal and a client mailbox are 3 accounts. Pro has no limit on accounts.
A fourth connection
Three calendars that all block each other need 6 connections. Pro has no limit on connections.
Changes faster than every 30 minutes
On Pro, Google and Outlook changes land within seconds, and iCloud, Fastmail and CalDAV changes land every minute.
Titles, descriptions and locations on copies
Pro can turn each one back on per calendar, or give copies a name of your choosing.
Choosing which events sync
Pro can leave out all-day events, focus time and out-of-office blocks, and change the copy range to anything from 1 week to 2 years.
More than one shareable link
Pro has no limit on links, and each link can have its own calendars, filters and level of detail.
More than 25 API or assistant calls a day
Pro has no daily cap on REST API and MCP calls.
Questions about the Free plan
Is Keeper.sh free?
Yes. Keeper.sh has a Free plan that costs $0 and covers 2 calendar accounts, 3 connections and 1 shareable calendar link. It is not a trial, and it needs no card.
What does the free plan include?
Keeper.sh's Free plan includes 2 calendar accounts, 3 connections, 1 shareable calendar link and 25 API or MCP calls a day. Changes land every 30 minutes, and copies cover one month back to two years ahead.
Can I sync Google Calendar and Outlook for free?
Yes. Keeper.sh's Free plan syncs a Google account and an Outlook account in both directions. That uses 2 accounts and 2 of the 3 connections.
Does the free plan work with iCloud?
Yes. Keeper.sh's Free plan connects iCloud with an app-specific password and can copy events both into and out of an iCloud calendar. Google Calendar, Outlook, Fastmail and CalDAV servers are covered on Free as well.
Is two-way sync free?
Yes. Each Keeper.sh connection runs one way, so two-way sync between two calendars is two connections, and the Free plan includes 3.
Do I need a credit card?
No. Keeper.sh's Free plan asks for an email address and a password, and no card.
How often does the free plan sync?
Keeper.sh's Free plan writes changes to your other calendars every 30 minutes, on every calendar service. On Pro, Google and Outlook changes land within seconds, and iCloud, Fastmail and CalDAV changes land every minute.
When do I need Pro?
You need Keeper.sh Pro for a third calendar account, a fourth connection, a second shareable link, event titles on copies, or changes that land faster than every 30 minutes. Pro is $5 a month or $45 a year.
Sync two calendars for free
Connect two calendar accounts and choose which way events should go. No card needed.