Zapier alternative for calendar sync: Keeper.sh vs Zapier

Zapier is an automation platform: a Zap can create an Outlook event each time a Google Calendar event is created or updated, and each action it completes uses a task. Keeper.sh is the Zapier alternative for keeping two calendars showing the same busy times, because one Keeper.sh connection handles new events, edits and deletions with no task count. 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.

The table compares the two for calendar sync, and links each Zapier figure to the Zapier page it comes from.

How a calendar Zap works

A Zap is a trigger followed by one or more actions. For calendars, Zapier's own example is the template "Create Microsoft Outlook events for new or updated events in Google Calendar": the Google Calendar trigger "New or Updated Event" starts the Zap, and the Outlook action creates an event with the fields you choose (Zapier, checked 10 November 2026).

• Cancellations are a separate trigger. "New or Updated Event" fires "when an event is created or updated (except when it's cancelled)", and "Event Cancelled" is its own trigger. Removing the copy when the original is deleted takes a second Zap with a delete action.
• Updating an existing copy takes a search step. Zapier's help centre says the "Update Event" dropdown lists "Only events created within the last 7 days", and older events need a find step to get the event's ID (common problems with Google Calendar, checked 10 November 2026). A trigger, a search and an update make a multi-step Zap, which starts on the Professional plan.
• Repeating events fire once per occurrence. The same page says: "If you have a repeated event and you update the series, the Zap will trigger once per event. So if the event repeats 10 times, it will trigger 10 times."

Two-way sync and loops

Zapier's Google Calendar and Outlook page describes one direction: changes made in Google Calendar are reflected in Outlook, and "direct updates or deletions made on the Outlook side are not pushed back to Google Calendar at this time" (Zapier).

Building the return path yourself means a second Zap, and Zapier's help centre describes what happens when two Zaps feed each other: "You have an action in one Zap that triggers another Zap and the second Zap has an action that triggers the first Zap". Its fix is to add unique data to the action and a Filter step that stops the loop (Zap is stuck in a loop, checked 10 November 2026).

Each Keeper.sh connection runs one way, so two-way sync is two connections. Keeper.sh marks each copy it writes and skips marked events when it reads a calendar, so two connections in opposite directions do not loop.

What each one costs for calendar sync

Zapier counts tasks: "When Zapier performs an action successfully, it counts as a task" (Zapier pricing). A two-step Zap uses one task for each event it creates, so the Free plan's 100 tasks a month cover 100 created events. Professional starts from $19.99 a month billed yearly ($29.99 billed monthly) and Team from $69 a month billed yearly ($103.50 billed monthly), and both prices rise with the task tier you pick.

Keeper.sh's plans are limited by calendar accounts and connections, not by a task count. Free covers 2 calendar accounts and 3 connections. Pro is $5 a month or $45 a year for unlimited calendars.

What a copied event shows

A Zap writes whatever you put in the action's fields. Zapier's "Create Detailed Event" action has fields for the summary, description, location, attendees, visibility and "Show me as Free or Busy", so you decide per Zap how much of the original travels.

Each Keeper.sh copy is a busy block named after the source calendar. The title, description and location are hidden by default, Pro can turn them back on per calendar, and guest lists are never copied.

What Zapier offers beyond calendar sync

• More than 9,000 other apps. Zapier "offers integrations for more than 9,000 apps" (Zapier pricing), so a calendar event can start a Zap in a spreadsheet, a CRM, a chat tool or a task manager.
• Logic per event. Filters, Paths and Formatter steps let a Zap act only on events that match a rule, or rewrite fields on the way through.
• Calendar actions other than copying. Zapier's Google Calendar actions include creating a calendar and moving an event to another calendar.
• Team features. The Team plan includes 25 users, shared Zaps and SAML SSO (Zapier pricing).

Zapier and Keeper.sh also work together: Keeper.sh keeps the calendars matched, and a Zap triggered by one of those calendars can post each new event to a Slack channel or add it as a row in Google Sheets.

When Keeper.sh fits

• You want the copy to follow edits and deletions. A Keeper.sh connection moves, shortens or removes the copy when the original changes.
• You want sync in both directions. Two connections give two-way sync, and both fit the Free plan.
• A calendar is on iCloud, Fastmail or a CalDAV server. Keeper.sh connects these directly.
• You want sync an assistant can manage. Keeper.sh has a REST API and an MCP server on both plans; the calendar sync features page lists both.

Create an account at Keeper.sh to add the first connection (sign up).

Step-by-step setup is in how to sync Google Calendar and Outlook and how to sync two Google Calendars.

Common questions about Zapier and calendar sync

Other comparisons

• CalendarBridge alternative
• CalendarBridge pricing explained
• Calendly with Keeper.sh
• Kalender Sync alternative
• Morgen alternative
• Notion Calendar alternative
• OGCS alternative
• OneCal alternative
• OneCal vs CalendarBridge
• Reclaim.ai alternative
• SyncDate alternative
• SyncGene alternative
• SyncThemCalendars alternative
• Best calendar sync tools compared