What does my birthday say about me?

Five traditions each have something to say about the day you were born. Here's what each one says for your date, and a written portrait that puts them together.

How seriously should you take it?

None of these systems has held up in controlled studies. The best-known test, Shawn Carlson's double-blind experiment published in Nature in 1985, found astrologers matched birth charts to personality profiles no better than chance. Their appeal is closer to a good personality quiz: a vocabulary for talking about yourself, and a prompt to notice which descriptions ring true and which don't.

A few birthday facts are measurable. Your birth month has small, well-documented effects through school starting ages: the "relative age effect", where the oldest children in a school year are over-represented in youth sports teams. The season you were born in also affects early exposure to sunlight and infections. Those are real, but small.

More from your birth date

Birthday calculatorEverything about one birth date, on one ticket Age calculatorExact age in years, months and days Days livedDays, hours, heartbeats and milestones What day was I born?Your birth weekday, worked out by hand Age on other planetsYour age in Mercury, Mars or Neptune years What generation am I?Boomer to Gen Beta, by birth year Birthday countdownLive timer + a shareable link Half birthdayThe date six months after your birthday Birthday message writerA card message built from their birth date

Questions people ask

What does my birthday say about my personality?

Different traditions read it differently: Western astrology through your sun and moon signs, Chinese astrology through your animal and element, numerology through your life path number, and folklore through your birth weekday, stone and flower. Enter your date to see all of them side by side.

Is the birthday portrait written by AI?

Yes. The facts are calculated exactly in your browser; the portrait is then written by an AI model that is told to use only those facts. Treat it as entertainment.

Does my birth month affect anything real?

Slightly. Research on the relative age effect shows children born just after a school-year cut-off are more likely to be picked for sports teams, and season of birth is linked to small differences in some health outcomes. Personality effects claimed by astrology have not been supported by studies.