Show contacts’ birthdays in Calendar on Mac
When you add birthdays to contact cards, you can see the birthdays on the Birthdays calendar in the Calendar app—just make sure Calendar preferences are set to show the Birthdays calendar.
Ask Siri. When you add a birthday to someone’s contact card, you can say something like: “When is Jane’s birthday?” Learn how to ask Siri.
The Birthdays calendar is updated automatically when you add or remove birthdays in Contacts.