What is the term for a Reddit user's account anniversary?

A Reddit user's account anniversary is called their Cake Day.

Cake Day occurs each year on the anniversary of the date a Reddit account was created. During that anniversary period, Reddit traditionally displays a small cake icon beside the user's name, making the celebration visible in posts and comments. The custom is one of Reddit's best-known pieces of community vocabulary.

The name comes from the familiar birthday-cake association: an account is treated as having a yearly “birthday.” It does not refer to the user's real-world birthday, the anniversary of joining a particular subreddit, or the date of a memorable post. It is tied specifically to account creation.

Cake Day is also a common source of playful interaction. Other Redditors may congratulate someone, make jokes about the cake icon, or use the occasion to share a particularly popular post. The exact display and duration of the icon have changed across Reddit's redesigns and apps, but the underlying meaning remains the same: the yearly anniversary of a Reddit account.