Weekday · Age · Milestones
What Day Was I Born?Find your weekday.
Enter your date of birth to see the weekday you were born, your age, moon phase, and more.
Birthday calculator
Consulting the lunar tables…
Your birthday results
Hours, minutes, and seconds are date-based approximations (birth treated as local midnight) because a birth time was not provided.
Approx. seconds alive
Assumes birth at local midnight.
Upcoming milestones
On this day
What's it all mean?
Curious about stones, signs, animals, weekdays, the moon, and generations? Pick a topic.
BirthstonesTraditions by birth month
Western zodiacTropical sign date ranges
Chinese zodiacTwelve-year animal cycle- Weekday birthdaysWhat each weekday means culturally
Moon phasesEight phases named for birth dates- GenerationsBirth-year cohort nicknames
Planetary alignmentScrub a Sun-centered orrery by date- Birthday guidesIdeas, gifts, and explanations
How we calculate
Weekday, age, and leap-year results use standard calendar math in your local time zone. Hours, minutes, and seconds are approximate because this calculator accepts a date only, not a birth time. World-population age shares use a static mid-2020s age-structure snapshot. Chinese zodiac animals change at Chinese New Year; Western signs, birthstones, moon phase, and generations follow the conventions described in our methodology.