The most common birthday is September 9.
Understanding Birthday Frequencies
While birthdays are celebrated throughout the year, some dates occur more frequently than others. Data indicates a clear pattern, with the early fall season, particularly September, standing out for its higher birth rates.
Top Common Birthdays
The top three most common birthdays are all found within the month of September, highlighting a concentrated period of births.
| Rank | Birthday Date |
|---|---|
| 1 | September 9 |
| 2 | September 19 |
| 3 | September 12 |
The September Phenomenon
Remarkably, the entire top 10 list of most common birthdays consists of dates ranging from September 9 to September 20. This trend can be attributed to a simple biological timeline: an average pregnancy lasts approximately 40 weeks from the last menstruation. Counting backward 40 weeks from September leads directly to the holiday season around December and January. This suggests a common conception period linked to festive times of the year.
