Add birthdays to Contacts on Mac
You can add a birthday to a contact’s card, including birthdays based on a lunar calendar (such as the Chinese, Hebrew, or Islamic lunar calendars).
In the Contacts app on your Mac, select a contact.
Click the Add button , then choose Birthday, or choose More Fields, then Lunar Birthday.
If an option is dimmed, it’s already on the card.
Enter the date, then click Done.
Ask Siri. After you add a birthday to someone’s contact card, you can say something like: “When is Jane’s birthday?” Learn how to ask Siri.