Google Calendar Event

The google calendar platform allows you to connect to your Google Calendars and generate binary sensors. The sensors created can trigger based on any event on the calendar or only for matching events. When you first setup this integration it will generate a new configuration file google_calendars.yaml in your configuration directory that will contain information about all of the calendars you can see. It also exposes a service to add an event to one of your Google Calendars.


Generate a Client ID and Client Secret on Google Developers Console.

  1. First go to the Google Developers Console
  2. The wizard will ask you to choose a project to manage your application. Select a project and click continue.
  3. Verify that your calendar API was enabled and click ‘Go to credentials’
  4. When it gets to the Page titled Add credentials to your project just click cancel.
  5. Navigate to APIs & Services (left sidebar) > Credentials
  6. Click on the field on the right of the screen, ‘CONFIGURE CONSENT SCREEN’, select “External” and create.
  7. Set the ‘Application Name’ (the name of the application asking for consent) to anything you want. We suggest “Home-Assistant”.
  8. Scroll to the bottom and save this page. You don’t have to fill out anything else here.
  9. Click on the menu item, Credentials, then click ‘Create credentials’ > OAuth client ID.
  10. Set the Application type to ‘Other’ (if not present, choose ‘TV and Limited Input’) and give this credential set a name (like “Home Assistant Credentials”) then click ‘Create’.
  11. You can now copy the client ID and client secret from the page that follows into a text editor temporarily as you will need to put these in your configuration.yaml file.
  12. Click on the menu item, Library, then search for “Google Calendar API” and enable it (if it isn’t already enabled automatically through this process).
  13. In order to access your client ID and client secret you can click the navigation menu (hamburger menu) in the top left corner navigate to ‘APIs & Services’ > Credentials and your credentials will appear under ‘OAuth 2.0 Client IDs’ with the name you created earlier
  14. Clicking on the name will reveal both the client ID and client secret that you will add to your configuration.yamlfile below

If you will later be adding more scopes than just the “Google Calendar API” to the OAuth for this application, you will need to delete your token file under your Home Assistant Profile. You will lose your refresh token due to the re-authenticating to add more API access. It’s recommended to use different authorizations for different pieces of Google.


If you are trying to switch to a new Google account then you would run into the following error message. Make sure to delete the existing .google.token file from your config folder and restart Home Assistant to try again.

‘oauth2client.client.HttpAccessTokenRefreshError: deleted_client: The OAuth client was deleted’


To integrate Google Calendar in Home Assistant, add the following section to your configuration.yaml file:

# Example configuration.yaml entry
  client_id: YOUR_CLIENT_ID
  client_secret: YOUR_CLIENT_SECRET

Configuration Variables


Use the client ID you generated in the Prerequisites stage.


Use the client secret you generated in the Prerequisites stage.

track_new_calendarboolean(Optional, default: true)

Will automatically generate a binary sensor when a new calendar is detected. The system scans for new calendars only on startup.

The next time you run or restart Home Assistant, you should find a new notification (the little bell icon in the lower left corner). Click on that notification it will give you a link and an authentication code. Click on that link to open a Google website where you should enter the code found in the notification. This will grant your Home Assistant service read-only access to all the Google Calendars that the account you authenticate with can read.

Calendar Configuration

Editing the google_calendars.yaml file.

A basic entry for a single calendar looks like:

- cal_id: "*****"
  - device_id: test_everything
    name: Give me everything
    track: true
- cal_id: "*****"
  - device_id: test_important
    name: Important Stuff
    track: true
    search: "#Important"
    offset: "!!"
  - device_id: test_unimportant
    name: UnImportant Stuff
    track: true
    search: "#UnImportant"

Configuration Variables


The Google generated unique id for this calendar.




Yes, you can have multiple sensors for a calendar!


The name that all your automations/scripts will use to reference this device.


What is the name of your sensor that you’ll see in the frontend.

trackbooleanRequired, default: true

Should we create a sensor true or ignore it false?


If set will only trigger for matched events.

offsetstring(Optional, default: !!)

A set of characters that precede a number in the event title for designating a pre-trigger state change on the sensor. This should be in the format of HH:MM or MM.

ignore_availabilityboolean(Optional, default: true)

Should we respect free/busy flags?

max_resultsinteger(Optional, default: 5)

Max number of entries to retrieve

From this we will end up with the binary sensors calendar.test_unimportant and calendar.test_important which will toggle themselves on/off based on events on the same calendar that match the search value set for each. You’ll also have a sensor calendar.test_everything that will not filter events out and always show the next event available.

But what if you only wanted it to toggle based on all events? Just leave out the search parameter.

If you use a # sign for search then wrap the whole search term in quotes. Otherwise everything following the hash sign would be considered a YAML comment.

Sensor attributes

  • offset_reached: If set in the event title and parsed out will be on/off once the offset in the title in minutes is reached. So the title Very important meeting #Important !!-10 would trigger this attribute to be on 10 minutes before the event starts.
  • all_day: true/false if this is an all day event. Will be false if there is no event found.
  • message: The event title with the search and offset values extracted. So in the above example for offset_reached the message would be set to Very important meeting
  • description: The event description.
  • location: The event Location.
  • start_time: Start time of event.
  • end_time: End time of event.

Service google.add_event

You can use the service google.add_event to create a new calendar event in a calendar. Calendar id’s can be found in the file google_calendars.yaml. All dates and times are in your local time, the integration gets your time zone from your configuration.yaml file.

Service data attribute Optional Description Example
calendar_id no The id of the calendar you want. *****
summary no Acts as the title of the event. Bowling
description yes The description of the event. Birthday bowling
start_date_time yes The date and time the event should start. 2019-03-10 20:00:00
end_date_time yes The date and time the event should end. 2019-03-10 23:00:00
start_date yes The date the whole day event should start. 2019-03-10
end_date yes The date the whole day event should end. 2019-03-11
in yes Days or weeks that you want to create the event in. “days”: 2

You either use start_date_time and end_date_time, or start_date and end_date, or in.

Using calendar in automations

A calendar can be used as an external scheduler for special events or reoccurring events instead of hardcoding them in automations.

Trigger as soon as an event starts:

      platform: state
      entity_id: calendar.calendar_name
      to: 'on'

By using specific text in the event title, you can set conditions to initiate particular automation flows on designated events while other events will be ignored.

For example, the actions following this condition will only be executed for events named ‘vacation’:

        condition: template
        value_template: "{{is_state_attr('calendar.calendar_name', 'message', 'vacation') }}"