Birthday Rarity Calculator
Discover how common or rare your birthday is compared to others throughout the year. Some birthdays are significantly more common than others!
Your Birthday Rarity Results
Most Common and Rare Birthdays
Most Common Birthdays
- September 9 - Many babies are born in September, about 9 months after the holiday season
- September 19 - Another popular September birthday
- September 12 - Fall births are generally more common
- September 17 - Mid-September continues to be a popular time
- July 7 - Summer is the second most popular birth season
Rarest Birthdays
- December 25 - Christmas Day has fewer births due to scheduled deliveries avoiding holidays
- January 1 - New Year's Day is another holiday with fewer births
- December 24 - Christmas Eve sees fewer births
- July 4 - Independence Day in the US has fewer scheduled deliveries
- February 29 - Leap Day only occurs once every four years
Factors Affecting Birthday Distribution
The distribution of birthdays throughout the year isn't random. Several factors influence when babies are born:
- Seasonal Conception Patterns: More babies are conceived during certain times of year, such as winter holidays
- Scheduled Deliveries: Doctors and patients often avoid scheduling induced labor or C-sections on weekends and holidays
- School Year Planning: Some parents plan pregnancies to have children born at certain times of the year
- Cultural Factors: Different cultures may have different patterns of birth timing
- Climate Effects: Extreme weather conditions can affect conception rates
Birthday Rarity FAQ
Why are some birthdays more common than others?
Birth patterns are influenced by seasonal conception rates, scheduled medical procedures, holidays, and cultural factors. September birthdays are common because they occur approximately 9 months after the winter holiday season.
Is having a rare birthday special?
Having a rare birthday can be considered special as fewer people share your birth date. However, the rarity often has more to do with medical scheduling and holidays than any cosmic significance.
How accurate is this calculator?
Our calculator uses data from birth records to determine birthday frequency. While patterns are generally consistent year to year, there can be slight variations based on the dataset used.