Two decades of birthdays, ranked

BDay Rank started with a simple question: is my birthday unusual? Everyone has a hunch — the December babies who feel forgotten, the September crowd who share a birthday with half their class — but the answer is sitting in public health records that almost nobody reads for fun.

This site turns 21 years of U.S. birth registrations into one picture. Every one of the 366 possible calendar dates gets an average, a rank and a colour, so you can see at a glance where your day falls: the amber-and-coral crush of early September or the quiet violet corners around the winter holidays.

What we found

The average calendar day sees about 11,174 American births. The busiest is 12,344 births/day and the quietest is 6,601 births/day — a gap of nearly two-to-one between the top and bottom of the calendar.

• Nine of the top ten days are in September, about 40 weeks after the holidays.
• The bottom of the list is almost entirely public holidays: Christmas, New Year's Day, the Fourth of July and Thanksgiving week.
• The 13th of every month runs slightly below its neighbours — a quiet, measurable trace of superstition in scheduled deliveries.

Who makes it

BDay Rank is a small independent project built by data-visualization enthusiasts. It is not affiliated with the CDC, the Social Security Administration or any news organization that publishes the underlying numbers.

How it is built

The site runs on Next.js with a PostgreSQL database holding the daily averages, the notable-birthday index and print orders. Every chart is hand-drawn SVG, and the downloadable images are rendered right in your browser, so nothing about your birthday is sent anywhere to make them.

Keep exploring

Read the methodology for the full recipe, browse the print shop, or send us a note if you spot something odd in the data.