user: findMeetingTimes

Namespace: microsoft.graph

Suggest meeting times and locations based on organizer and attendee availability, and time or location constraints specified as parameters.

If findMeetingTimes cannot return any meeting suggestions, the response would indicate a reason in the emptySuggestionsReason property. Based on this value, you can better adjust the parameters and call findMeetingTimes again.

The algorithm used to suggest meeting times and locations undergoes fine-tuning from time to time. In scenarios like test environments where the input parameters and calendar data remain static, expect that the suggested results may differ over time.

This API is available in the following national cloud deployments.

Global service US Government L4 US Government L5 (DOD) China operated by 21Vianet

Permissions

Choose the permission or permissions marked as least privileged for this API. Use a higher privileged permission or permissions only if your app requires it. For details about delegated and application permissions, see Permission types. To learn more about these permissions, see the permissions reference.

Permission type Least privileged permissions Higher privileged permissions
Delegated (work or school account) Calendars.Read.Shared Calendars.ReadWrite.Shared
Delegated (personal Microsoft account) Not supported. Not supported.
Application Not supported. Not supported.

HTTP request

POST /me/findMeetingTimes
POST /users/{id|userPrincipalName}/findMeetingTimes

Request headers

Name Value
Authorization Bearer {token}. Required. Learn more about authentication and authorization.
Prefer: outlook.timezone A string representing a specific time zone for the response, for example, "Pacific Standard Time". Optional. UTC is used if this header is not specified.

Request body

All the supported parameters are listed below. Depending on your scenario, specify a JSON object for each of the necessary parameters in the request body.

Parameter Type Description
attendees attendeeBase collection A collection of attendees or resources for the meeting. Since findMeetingTimes assumes that any attendee who is a person is always required, specify required for a person and resource for a resource in the corresponding type property. An empty collection causes findMeetingTimes to look for free time slots for only the organizer. Optional.
isOrganizerOptional Edm.Boolean Specify True if the organizer doesn't necessarily have to attend. The default is false. Optional.
locationConstraint locationConstraint The organizer's requirements about the meeting location, such as whether a suggestion for a meeting location is required, or there are specific locations only where the meeting can take place. Optional.
maxCandidates Edm.Int32 The maximum number of meeting time suggestions to be returned. Optional.
meetingDuration Edm.Duration The length of the meeting, denoted in ISO8601 format. For example, 1 hour is denoted as 'PT1H', where 'P' is the duration designator, 'T' is the time designator, and 'H' is the hour designator. Use M to indicate minutes for the duration; for example, 2 hours and 30 minutes would be 'PT2H30M'. If no meeting duration is specified, findMeetingTimes uses the default of 30 minutes. Optional.
minimumAttendeePercentage Edm.Double The minimum required confidence for a time slot to be returned in the response. It is a % value ranging from 0 to 100. Optional.
returnSuggestionReasons Edm.Boolean Specify True to return a reason for each meeting suggestion in the suggestionReason property. The default is false to not return that property. Optional.
timeConstraint timeConstraint Any time restrictions for a meeting, which can include the nature of the meeting (activityDomain property) and possible meeting time periods (timeSlots property). findMeetingTimes assumes activityDomain as work if you don't specify this parameter. Optional.

The following table describes the activityDomain restrictions you can further specify in the timeConstraint parameter.

activityDomain value Suggestions for meeting times
work Suggestions are within the user's work hours which are defined in the user’s calendar configuration and can be customized by the user or administrator. The default work hours are Monday to Friday, 8am to 5pm in the time zone set for the mailbox. This is the default value if no activityDomain is specified.
personal Suggestions are within the user's work hours, and Saturday and Sunday. The default is Monday to Sunday, 8am to 5pm, in the time zone setting for the mailbox.
unrestricted Suggestions can be from all hours of a day, all days of a week.
unknown Do not use this value as it will be deprecated in the future. Currently behaves the same as work. Change any existing code to use work, personal or unrestricted as appropriate.

Based on the specified parameters,findMeetingTimes checks the free/busy status in the primary calendars of the organizer and attendees. The action calculates the best possible meeting times, and returns any meeting suggestions.

Response

If successful, this method returns 200 OK response code and a meetingTimeSuggestionsResult in the response body.

A meetingTimeSuggestionsResult includes a collection of meeting suggestions and an emptySuggestionsReason property. Each suggestion is defined as a meetingTimeSuggestion, with attendees having on the average a confidence level of 50% to attend, or a specific % that you have specified in the minimumAttendeePercentage parameter.

By default, each meeting time suggestion is returned in UTC.

If findMeetingTimes cannot return any meeting suggestions, the response would indicate a reason in the emptySuggestionsReason property. Based on this value, you can better adjust the parameters and call findMeetingTimes again.

The confidence of a meeting suggestion

The confidence property of a meetingTimeSuggestion ranges from 0% to 100%, and represents the chance that all the attendees attend the meeting, based on each of their individual free/busy status:

  • For each attendee, a free status for a specified meeting time period corresponds to 100% chance of attendance, unknown status 49%, and busy status 0%.
  • The confidence of a meeting time suggestion is computed by averaging the chance of attendance over all the attendees specified for that meeting.
  • You can use the minimumAttendeePercentage optional parameter for findMeetingTimes to specify only meeting time suggestions of at least certain confidence level should be returned. For example, you can specify a minimumAttendeePercentage of 80% if you want only suggestions that have an 80% chance or more that all the attendees are attending. If you do not specify minimumAttendeePercentage, findMeetingTimes assumes a value of 50%.
  • If there are multiple meeting time suggestions, the findMeetingTimes action first orders the suggestions by their computed confidence value from high to low. If there are suggestions with the same confidence, the action then orders these suggestions chronologically.

As an example, if a meeting time suggestion involves 3 attendees with the following free/busy status:

Attendee Free/busy status % Chance of attendance
Dana Free 100%
John Unknown 49%
Samantha Busy 0%

Then the confidence of the meeting time suggestion, which is the average chance of attendance, is (100% + 49% + 0%)/3 = 49.66%.

If you specify a minimumAttendeePercentage of 80% in a findMeetingTimes operation, because 49.66% < 80%, the operation will not suggest this time in the response.

Example

The following example shows how to find time to meet at a pre-determined location, and request a reason for each suggestion, by specifying the following parameters in the request body:

  • attendees
  • locationConstraint
  • timeConstraint
  • isOrganizerOptional
  • meetingDuration
  • returnSuggestionReasons
  • minimumAttendeePercentage

By setting the returnSuggestionReasons parameter, you also get an explanation in the suggestionReason property for each suggestion, if findMeetingTimes returns any suggestion.

Notice that the request specifies time in the PST time zone. By default, the response returns meeting time suggestions in UTC. You can use the Prefer: outlook.timezone request header to specify PST as well for the time values in the response.

Request

Here is the example request.

POST https://graph.microsoft.com/v1.0/me/findMeetingTimes
Prefer: outlook.timezone="Pacific Standard Time"
Content-Type: application/json

{
  "attendees": [
    {
      "type": "required",
      "emailAddress": {
        "name": "Alex Wilbur",
        "address": "alexw@contoso.com"
      }
    }
  ],
  "locationConstraint": {
    "isRequired": false,
    "suggestLocation": false,
    "locations": [
      {
        "resolveAvailability": false,
        "displayName": "Conf room Hood"
      }
    ]
  },
  "timeConstraint": {
    "activityDomain":"work",
    "timeSlots": [
      {
        "start": {
          "dateTime": "2019-04-16T09:00:00",
          "timeZone": "Pacific Standard Time"
        },
        "end": {
          "dateTime": "2019-04-18T17:00:00",
          "timeZone": "Pacific Standard Time"
        }
      }
    ]
  },
  "isOrganizerOptional": "false",
  "meetingDuration": "PT1H",
  "returnSuggestionReasons": "true",
  "minimumAttendeePercentage": 100
}
Response

Here is an example response. Note: The response object shown here might be shortened for readability.

HTTP/1.1 200 OK
Content-type: application/json
Preference-Applied: outlook.timezone="Pacific Standard Time"

{
    "@odata.context": "https://graph.microsoft.com/v1.0/$metadata#microsoft.graph.meetingTimeSuggestionsResult",
    "emptySuggestionsReason": "",
    "meetingTimeSuggestions": [
        {
            "confidence": 100,
            "order": 1,
            "organizerAvailability": "free",
            "suggestionReason": "Suggested because it is one of the nearest times when all attendees are available.",
            "attendeeAvailability": [
                {
                    "availability": "free",
                    "attendee": {
                        "emailAddress": {
                            "address": "alexw@contoso.com"
                        }
                    }
                }
            ],
            "locations": [
                {
                    "displayName": "Conf room Hood"
                }
            ],
            "meetingTimeSlot": {
                "start": {
                    "dateTime": "2019-04-18T16:00:00.0000000",
                    "timeZone": "Pacific Standard Time"
                },
                "end": {
                    "dateTime": "2019-04-18T17:00:00.0000000",
                    "timeZone": "Pacific Standard Time"
                }
            }
        },
        {
            "confidence": 100,
            "order": 2,
            "organizerAvailability": "free",
            "suggestionReason": "Suggested because it is one of the nearest times when all attendees are available.",
            "attendeeAvailability": [
                {
                    "availability": "free",
                    "attendee": {
                        "emailAddress": {
                            "address": "alexw@contoso.com"
                        }
                    }
                }
            ],
            "locations": [
                {
                    "displayName": "Conf room Hood"
                }
            ],
            "meetingTimeSlot": {
                "start": {
                    "dateTime": "2019-04-18T08:00:00.0000000",
                    "timeZone": "Pacific Standard Time"
                },
                "end": {
                    "dateTime": "2019-04-18T09:00:00.0000000",
                    "timeZone": "Pacific Standard Time"
                }
            }
        },
        {
            "confidence": 100,
            "order": 3,
            "organizerAvailability": "tentative",
            "suggestionReason": "Suggested because it is one of the nearest times when all attendees are available.",
            "attendeeAvailability": [
                {
                    "availability": "free",
                    "attendee": {
                        "emailAddress": {
                            "address": "alexw@contoso.com"
                        }
                    }
                }
            ],
            "locations": [
                {
                    "displayName": "Conf room Hood"
                }
            ],
            "meetingTimeSlot": {
                "start": {
                    "dateTime": "2019-04-18T15:00:00.0000000",
                    "timeZone": "Pacific Standard Time"
                },
                "end": {
                    "dateTime": "2019-04-18T16:00:00.0000000",
                    "timeZone": "Pacific Standard Time"
                }
            }
        },
        {
            "confidence": 100,
            "order": 4,
            "organizerAvailability": "tentative",
            "suggestionReason": "Suggested because it is one of the nearest times when all attendees are available.",
            "attendeeAvailability": [
                {
                    "availability": "free",
                    "attendee": {
                        "emailAddress": {
                            "address": "alexw@contoso.com"
                        }
                    }
                }
            ],
            "locations": [
                {
                    "displayName": "Conf room Hood"
                }
            ],
            "meetingTimeSlot": {
                "start": {
                    "dateTime": "2019-04-18T09:00:00.0000000",
                    "timeZone": "Pacific Standard Time"
                },
                "end": {
                    "dateTime": "2019-04-18T10:00:00.0000000",
                    "timeZone": "Pacific Standard Time"
                }
            }
        },
        {
            "confidence": 100,
            "order": 5,
            "organizerAvailability": "tentative",
            "suggestionReason": "Suggested because it is one of the nearest times when all attendees are available.",
            "attendeeAvailability": [
                {
                    "availability": "free",
                    "attendee": {
                        "emailAddress": {
                            "address": "alexw@contoso.com"
                        }
                    }
                }
            ],
            "locations": [
                {
                    "displayName": "Conf room Hood"
                }
            ],
            "meetingTimeSlot": {
                "start": {
                    "dateTime": "2019-04-18T12:00:00.0000000",
                    "timeZone": "Pacific Standard Time"
                },
                "end": {
                    "dateTime": "2019-04-18T13:00:00.0000000",
                    "timeZone": "Pacific Standard Time"
                }
            }
        }
    ]
}