How rare is your birthday?

Pick a date. We rank it against all 366 days of the year.

Pick your birthdayJanuary
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Children in party hats crowding around a giant wall calendar beside a birthday cake
The short answer

September 9 is the most common. December 25 is the rarest.

An average September 9 brings 11,900 babies in the United States. An average December 25 brings 6,535 — 1.8 times fewer.

The five most common

  1. #1September 911,900+10.0%
  2. #2September 1911,790+9.0%
  3. #3July 711,772+8.8%
  4. #4September 1211,764+8.7%
  5. #5September 1011,745+8.6%

The five rarest

  1. #366December 256,535−39.6%
  2. #365January 17,731−28.5%
  3. #364December 248,009−26.0%
  4. #363July 48,692−19.7%
  5. #362January 29,150−15.4%
Every date at once

The year has a shape

Nine of the ten busiest days of the year fall in September. The four quietest are December 25, January 1, December 24 and July 4. See every birth month.

JanJFebFMarMAprAMayMJunJJulJAugASepSOctONovNDecD151015202530

RarestMost common

Superstition

The 13th is the day nobody books

The 13th runs −1.7% against an average day while the days on either side of it run +1.0%. It is the quietest of the three in all twelve months of the year.

  • 11th+0.1%
  • 12th+0.9%
  • 13th−1.7%
  • 14th+1.1%
  • 15th+1.1%

Every 13th of the year against an average day in the United States.

A black cat sitting on a table next to a birthday cake while a child peeks over the edge
Things people get wrong

Four dates that misbehave

Not the rarestFebruary 29#353 of 366 · −8.4% against an average dayLeap day is the famous answer and the wrong one. Counted on the days it actually happens, 13 other dates still see fewer births.The rarest of allDecember 25#366 of 366 · −39.6% against an average dayHospitals postpone as many births as they can that day, so fewer babies arrive.Quieter than its reputationOctober 31#355 of 366 · −9.5% against an average dayParents who can choose the day tend to skip Halloween.Busier than other holidaysFebruary 14#90 of 366 · +3.7% against an average dayUnlike most holidays, more babies arrive on Valentine's Day than on an average day.
Around the world

Is the most common birthday the same everywhere?

Not quite. Each country peaks on its own day, from January 3 in Argentina to December 27 in Chile.

September 20the most common birthday across all 29 countries
17 of 29countries have their most common birthday in September
16 of 29countries have Christmas Day as their rarest birthday
See all 29 countries →

So, how rare is yours?

Find your dateJanuary
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Every one of the 366 dates counted the same way. How we count.