January in the birth records
January accounts for 5,072,588 births, or 8.16% of the 62,187,024 records in the SSA 2000–2014 sample. Within this month, January 24 is the most common date, ranked #151 nationally. January 1 has the fewest total records and ranks #364. The table above includes all 31 dates, not just those two extremes.
What makes this month worth a closer look
January starts with a striking outlier. New Year’s Day sits near the rare end of the calendar, while the dates later in the month have much larger counts. A statement that “January birthdays are rare” misses this variation: the first day and the middle of the month are different comparisons. January 2 is also relatively low in this sample. Read the individual rows before applying the month’s overall pattern to your own birthday.
The holiday is a useful calendar landmark, but these daily counts do not record parents’ scheduling decisions or medical circumstances. They show a pattern, not its cause. Compare the year-end rows in December to see both sides of the holiday boundary.
Read your row and make a card
Rank #1 is most common across all 366 dates. “1 in” divides all birth records by the records for that specific date; the daily-average column divides by the number of times the date occurred. A higher “rarer than” percentage means more other dates had higher counts. These are different ways of describing the same historical sample, not estimates of everyone alive today.
Select your date in the table to open the birthday calculator. Save a portrait or landscape result, or combine it with your name. The complete methodology and original FiveThirtyEight source stay available for anyone who wants to check the numbers.