Birthday tool
How common is your birthday?
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Tip: tap any square to see that date.
🎉 10 most common birthdays
- September 9#1 · 12,344/day
- September 19#2 · 12,285/day
- September 12#3 · 12,282/day
- September 17#4 · 12,201/day
- September 10#5 · 12,190/day
- September 20#6 · 12,162/day
- July 7#7 · 12,147/day
- September 16#8 · 12,114/day
- September 15#9 · 12,126/day
- September 18#10 · 12,112/day
💎 10 rarest birthdays
- December 25#366 · 6,601/day
- January 1#365 · 7,827/day
- December 24#364 · 8,103/day
- July 4#363 · 8,825/day
- January 2#362 · 9,356/day
- December 26#361 · 9,599/day
- November 27#360 · 9,770/day
- November 23#359 · 9,919/day
- November 25#358 · 10,001/day
- October 31#357 · 10,030/day
Where these numbers come from
Real US birth counts for every day from 1994–2014 (21 years, 85,712,738 births), published by FiveThirtyEight: US_births_1994-2003_CDC_NCHS.csv (CDC National Center for Health Statistics) and US_births_2000-2014_SSA.csv (Social Security Administration). The files overlap in 2000–2003; we use CDC/NCHS for 1994–1999 and SSA for 2000–2014 so each year counts once.
Method: for each year we divide each day's births by that year's daily average (so bigger and smaller years count equally), then average that ratio for each calendar date across the years it exists. February 29 is averaged over the 5 leap years only (1996, 2000, 2004, 2008, 2012), so it isn't penalized for existing once every four years. Dates are ranked 1–366. Averaging over many years also evens out the weekday effect (fewer births on weekends). This is for fun, not a forecast.
Expecting? Try our due date calculator or the baby name generator.