Generally Available: You can now filter calendar list entries to show only calendars belonging to your organization using the new showOwnOrganizationOnly parameter in the calendarList.list endpoint.

To learn more, see the calendarList.list documentation.

Generally available: We are introducing a new calendar access level: writerWithoutPrivateAccess. This new level permits read and write access to events that aren't private on a calendar, and shows private events as busy blocks. Users with this role cannot modify or see details for private events.

For more details, see the ACL resource documentation.

Change

To ensure consistent visibility across recurring events, changing the visibility of a single instance in the Google Calendar API can affect all instances of the series:

• More restrictive changes propagate: If you change the visibility of one instance of a recurring event to a more restrictive setting (for example, from public to private), the change is propagated to all instances of the recurring event.
• Less restrictive changes are ignored: If you attempt to change the visibility of one instance of a recurring event to a less restrictive setting (for example, from private to public), the change is ignored and the visibility remains unchanged. To make a recurring event less restrictive, you must update the parent recurring event.

For more information, see Share calendars and events and the events resource reference.

Feature

Generally Available: The Google Calendar API now provides full support for custom labels and colors, allowing users to categorize events with a flexible palette beyond the previously fixed set of colors.

You can now list and modify labels on a calendar using the labelProperties on the Calendars resource.

Then, you can assign a label to an event by setting the ID of the label to eventLabelId on the Events resource.

Note that, in order to enable the labels feature, you must set the eventLabelVersion request parameter to 1 on import, insert, patch and update operations on Events resources.

To learn more, see the Manage custom labels and colors guide.

Generally Available: Workspace administrators can now use the Google Calendar API to programmatically transfer the ownership of secondary calendars between users within the same organization.

To learn more, see the Calendars.transferOwnership method documentation.

Generally available starting June 29, 2026: We are introducing a new calendar access level: writerWithoutPrivateAccess. This new level permits read and write access to events that aren't private on a calendar, and shows private events as busy blocks. Users with this role cannot modify or see details for private events.

Generally Available: Updates to Calendar API usage quotas

A new tiering model with updates to API usage quotas will start to roll out. For more information, see Google Workspace standardized model for agent tools and APIs.

Developer Preview: The Model Context Protocol (MCP) server for Google Calendar is now available in developer preview. MCP is an open protocol that enables seamless integration between AI applications and your calendars. By configuring the Calendar MCP server, you enable AI agents to securely read your schedule and take actions, such as creating, updating, or deleting events.

For example, you can ask your AI agent: "When is my next meeting with Ariel?"

To get started with the Calendar MCP server, see the following documentation:

• Set up the Calendar MCP server
• Calendar MCP tool reference

To find more available MCP servers, see Model Context Protocol (MCP) servers in Google Workspace.

We have updated the guidance for using Google Meet conferences on Google Calendar events.

Reusing Google Meet codes across different events can cause access issues, and can expose meeting details to unintended users. We recommend that you generate a new conference using the createRequest field for every new event.

For more information about using events with the Calendar API, see the documentation for the events resource.

Generally available starting November 10, 2025:

Secondary calendars will now have a single data owner. This applies to both existing and newly created calendars. In the Calendar API, the data owner's email address will be in the read-only dataOwner field in the Calendars and CalendarList resources.

To prevent unintended actions and undesired states, the following new restrictions apply:

• Only the data owner can delete secondary calendars.
• The data owner's access level cannot be changed from the default owner access.
• The data owner cannot remove an owned calendar from their calendar list. They can hide it from their UI.

When a new secondary calendar is created, the authenticated user that makes the request is the data owner. We recommend that you use user authentication to create secondary calendars. Data ownership can be transferred in the Google Calendar UI.

For more details, see the documentation for Calendars and CalendarList closer to November 10.

You can now access birthday and other special events that are automatically created from Google Contacts using the Calendar API.

Birthday events now have birthdayProperties that show birthday-specific event data, such as the type of the special event, whether it's a birthday, an anniversary, or another significant date, and the contact that the event is linked to. You can use the contact as a resource name in the People API to fetch contact details.

To learn more, see the developer guide for the birthday event type.

Generally available starting September 17, 2024: Create and manage birthdays directly within Google Calendar. Birthdays are exposed in the Calendar API as a new eventType called "birthday" which distinguishes special all-day events with an annual recurrence. Birthday events support a limited set of event properties.

You can filter by the birthday event type using the events.list() and events.watch() methods. If no type filters are specified, all event types including birthdays are returned.

To learn more, see our developer guide about working with the birthday event type.

The following changes to events from Gmail take effect on May 30, 2024:

• Events from Gmail use fromGmail instead default as the value for the eventType field. You can filter by this new event type using the events.list() and events.watch() methods.
• Events from Gmail use the email address of the email recipient as the event organizer instead of unknownorganizer@calendar.google.com.
• You can only update the event properties, such as reminders, color ID, visibility, status, and extended properties of Event resources with the event type fromGmail.

For details, see the Calendar API Events reference documentation.

The following change takes effect on June 3, 2024:

For batch operations on Event resources, a batched item returns an HTTP 409 Conflict status code if the batch operation can't successfully execute this item due to conflicts with other requested batched items.

Suggested action: Exclude all successfully finished and failed batched items and retry remaining items in a different batch operation or by using single event operations.

For more information, see Handle API errors.

The following changes will take effect on March 11, 2024:

• The use of event type filters will be considered when reviewing quota increase requests. Before you request a quota increase, make sure you specify the event types you need as a parameter for your application.
• Both events.list and events.watch will use the same default event type filter.
• To help with error handling, improved error messages will be returned when unsupported operations are attempted on special event types, such as working location, out-of-office, and focus time events.

For more information, refer to the following:

• Manage focus time, out of office, and working location events
• Manage quotas

Generally available: The events.watch() method now supports the eventTypes field as a query parameter so that you can subscribe to changes about specific Calendar events, such as working location, out-of-office, or focus time events. For details, see the reference documentation.

To fix a bug that prevented events of eventType != 'default' from importing, we updated the code sample in Populate a team vacation calendar, the popular Apps Script + Calendar API solution. Review the code change in GitHub.

Generally available: Reading and updating working locations using the Google Calendar API is now generally available. For details, see Manage working locations for Google Calendar users.

Developer Preview: The Google Calendar API now supports reading and updating working locations. For details, see Manage working locations for Google Calendar users.

The Calendar API now supports custom attachments. See Calendar add-ons for more information.

The Calendar API now exposes a new eventType. The new type is called focusTime and allows users of the API to distinguish the special focus time events. For more information, see the API reference.

Two new quotas now exist for the Calendar API in addition to the general Calendar usage limits:

• Per minute per project.
• Per minute per project per user.

See Manage quotas for more information.

Starting today, all existing and new out of office events will be updated to set the organizer to unknownorganizer@calendar.google.com instead of the Calendar owner. It may take 2-3 weeks for this change to fully roll out.

Feature

You can use the calendarId from the API endpoint https://www.googleapis.com/calendar/v3/calendars/calendarId to identify the owner of the out of office event.

The Calendar API now exposes a new field for events. The new field is called eventType and allows users of the API to distinguish special event types, such as outOfOffice. For more information, see the API reference.

From now, we require conferenceData to be consistent with conferenceData.conferenceSolution.key.type; meaning only Google Meet calls can have conferenceData.conferenceSolution.key.type set to hangoutsMeet. All 3P video conference providers are expected to set conferenceData.conferenceSolution.key.type to addOn.

We stopped auto-populating Meet for API calls (such as Events.insert) to prevent Meet conferences being added unintentionally via 3rd parties.

Fixed

Meet video conferences should be added explicitly using the following existing parameters:

1. Set conferenceDataVersion query parameter to 1.
2. Set conferenceData.createRequest event property as follows:
   • conferenceData.createRequest.conferenceSolutionKey.type to hangoutsMeet.
   • conferenceData.createRequest.requestId to unique request id.

Service accounts created on or after March 2, 2020 are only able to invite guests using domain-wide delegation of authority.

The Calendar API allows attaching a conference data of type addOn to a new or existing event using Events.insert or Events.update methods.

Starting on January 7, 2019, notifications and reminders using the sms method type will be ignored. The API calls setting such notifications and reminders will still succeed and modify all the other fields.

Since Calendar offers in-app notifications, you can still get notified, regardless of your device or connection. For more information see Google Calendar SMS notifications to be removed.

The Calendar API now supports four new OAuth scopes. The scopes allow your application to limit access to only the data you really need. See Authorizing Google Calendar API Requests for more details.

A more flexible approach to sending event change notifications is now available through the sendUpdates parameter. The new parameter lets you set event change notifications to do one of the following:

• Notify all the event guests.
• Notify only the guests who are not using Google Calendar.
• Completely suppress the notifications, for example, during a migration.

Now it is possible to always keep in sync guests who use other calendaring systems, without sending too many non-mandatory emails to Google Calendar users.

Support for the JSON-RPC protocol and Global HTTP batch endpoints has been deprecated, and will be fully discontinued on March 25, 2019. This change is being made to the Google API infrastructure and as such affects multiple Google APIs, including Calendar v3.

For more information and migration instructions, see the Discontinuing support for JSON-RPC and Global HTTP Batch Endpoints blog post.