April in the birth records
April accounts for 4,960,750 births, or 7.98% of the 62,187,024 records in the SSA 2000–2014 sample. Within this month, April 4 is the most common date, ranked #111 nationally. April 1 has the fewest total records and ranks #354. The table above includes all 30 dates, not just those two extremes.
What makes this month worth a closer look
April has 30 distinct month-and-day combinations in every year of this dataset. Unlike leap day, each April row has fifteen occurrences. That makes the total-birth and births-per-occurrence order identical within the month, even though one measure describes all records and the other describes an average date.
April 1 is an easy date to remember, but being memorable is different from being statistically uncommon. Its row gives a count-based answer. Easter can fall in March or April on different dates from year to year; a calendar-date average mixes those holiday and non-holiday years together. It cannot isolate an Easter effect. Compare the adjacent March table using the same source years.
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.