How to calculate and show ages by birthdays on Outlook calendar?

To calculate each contact’s age and show the age in the subject of the related recurring appointment in the Outlook calendar, please do as follows:

1. Open the default calendar folder, and press "Alt" + "F11" keys to open the "Microsoft Visual Basic for Applications" window.

2. Click "Insert" > "Module", and then paste the following VBA code into the new module window.

VBA: Calculate and show contacts’ ages in Outlook calendar

Option Explicit
Public Sub UpdateAges()
Dim xOlApp As Outlook.Application
Dim xOlFolder As Outlook.Folder
Dim xOlItems As Outlook.Items
Dim xAppointmentItem As AppointmentItem
Dim xAge As Integer
Dim xOlProp As Outlook.UserProperty
Set xOlApp = Outlook.Application
Set xOlFolder = Session.GetDefaultFolder(olFolderCalendar)
Set xOlItems = xOlFolder.Items
For Each xAppointmentItem In xOlItems
If (InStr(1, xAppointmentItem.Subject, "Birthday") Or InStr(1, xAppointmentItem.Subject, "Anniversary")) And xAppointmentItem.IsRecurring = True Then
With xAppointmentItem
If xAppointmentItem.UserProperties("Original Subject") Is Nothing Then
Set xOlProp = xAppointmentItem.UserProperties.Add("Original Subject", olText, True)
xOlProp.Value = .Subject
.Save
End If
xAge = DateDiff("yyyy", .Start, Date)
.Subject = .UserProperties("Original Subject") & " (" & xAge & " in " & Format(Date, "yyyy") & ")"
.Save
End With
End If
Next
Set xAppointmentItem = Nothing
Set xOlItems = Nothing
Set xOlFolder = Nothing
Set xOlApp = Nothing
End Sub

3. Press "F5" or click the "Run" button to execute the VBA.

When you return to the default calendar, you will see each contact’s age calculated and displayed in the subject of the recurring birthday appointment. See screenshot:

Notes:
(1) In the subject of a contact’s recurring birthday appointment, the contact’s age is shown inside parentheses, such as (41 in 2017), where 41 is the age, and 2017 is the current year.
(2) If you change a contact’s birthday in the contact folder, the displayed age will be removed from the calendar automatically.
(3) This VBA works with the default Outlook calendar only.

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