Birthday rarity calculator
Find your birthday rarity score
Select your birth date and country. You will get a rarity score, exact rank, modeled frequency, month context, and a fun profile with your zodiac sign, birthstone, birth flower, weekday, next birthday, countdown, and famous people born on the same date.
Your result
January 1 birthday rarity
January 1, 2001 is 69% rarer than average in the United States model.
This birthday is exceptionally rare in the calendar model.
A little more birthday fun
Your Birthday Profile
Here are the calendar traditions and countdown details connected with January 1, 2001.
New Year's Day Rarity
January 1 is often treated as a rare birthday because it lands on a major holiday and scheduled deliveries are less likely.
Your zodiac, just for fun
♑ Capricorn
In astrology, Capricorn is often described as dependable, goal-minded, and willing to keep going when a task takes time.
Astrology is a tradition rather than a scientific personality test, so enjoy this as a playful part of your birthday profile.
January birthday details
January begins the calendar year and is traditionally linked with garnet, carnations, and snowdrops.
January runs a little quieter than the full-year average in this country model. Its calendar dates average about 0.235% of births each in the modeled table, which is 14% rarer than the full-year average.
Your date in the model
January 1 represents about 0.086% of births in this country table, or about 0.86 per 1,000.
Why the year matters
Your birth year confirms the date, tells us which weekday you were born on, and identifies moving holidays. The rarity score itself remains based on your month and day.
Shared birthdays are surprisingly likely
In a group of 23 people, there is roughly a 50 percent chance that two people share a birthday. Your score compares dates; it does not mean nobody else shares yours.
Birthday twins in the spotlight
Famous people born on January 1
Meet some well-known people who share your month and day. Their birth years may differ, but the birthday date is the same.
Author
J. D. Salinger
Born January 1, 1919
The author is best known for The Catcher in the Rye and a small body of influential short fiction.
DJ and music pioneer
Grandmaster Flash
Born January 1, 1958
The hip-hop pioneer helped shape turntablism and was inducted into the Rock & Roll Hall of Fame with the Furious Five.
Actor
Verne Troyer
Born January 1, 1969
The actor became widely recognized for playing Mini-Me in the Austin Powers film series.
Explore birthday rarity
Start with the most useful birthday guides
See the dates at both ends of the calendar and learn how birthday patterns are compared.
Rarest birthdays
See which dates rank toward the rare end of the calendar and why Leap Day needs special treatment.
View rare birthdaysMost common birthdays
Explore the busier dates of the year and the seasonal patterns that can shape birthday frequency.
View common birthdaysBirthday statistics
Compare rare and common dates, monthly patterns, and the main results across all six country models.
Read birthday statisticsAcross the six country models
The main birthday patterns are easy to compare
The exact percentages vary by country, but the current models share several broad patterns.
These are modeled comparisons, not official national birth totals. The birthday statistics page shows the full country and month tables.
More birthday calculators
Find your birthday milestones
Discover the special dates and number patterns connected with your birthday.
Understanding your score
What makes a birthday rare?
Birthdays are not spread perfectly evenly across the calendar. Some seasons have more births than others, while major holidays and days affected by scheduling can have fewer. The calculator compares your date with the other calendar dates in the selected country model and converts that position into a birthday rarity score.
A higher score means the date appears toward the rarer end of the selected model. A lower score means it appears toward the busier end. The rank, percentage, and score all describe the same exact month-and-day comparison.
February 29 is also different from every recurring date because it only appears in leap years. Its calendar rarity and its birthday-frequency ranking are related ideas, but they are not exactly the same measurement.
Special birthday guides
Birthdays that already come with a story
Holiday and calendar-themed birthdays often feel especially memorable, whether or not they are the very rarest dates.
Famous birthdays
See who shares an unusual date
Birthday wording
Find the right birthday message
More rarity calculators
Curious about more than birthdays?
Explore two related calculators created for names and eye colours.
Birthday rarity questions
Frequently asked questions
Is February 29 the rarest birthday?
Yes for calendar rarity: February 29 only appears in leap years. The ranking guides also show the rarest annually recurring date so Leap Day can be separated from dates that return every year.
What does a birthday rarity score mean?
The score shows where your month and day fall compared with the other dates in the selected country model. A score closer to 100 falls toward the rarer end.
Why does the calculator ask for my birth year?
The year validates dates such as February 29 and helps the page identify moving holidays that landed on your birthday. It does not change the main month-and-day rarity score.
Why are some birthdays more common?
Birth patterns can vary by season, holidays, scheduling practices, and country. That is why birthday-frequency estimates are not perfectly even across the year.