While National Pie Day is January 23rd, March 14th, 3.14, is National Pi Day.
The date format 3.14 is the same as the first three digits of pi. The first 10 digits are 3.1415926535.
There are many more: Pi has been calculated to more than one trillion digits beyond its decimal point.
Some people are obsessed with memorizing as many digits of pi as possible. The Guinness Book Of World Records names the record holder as a man named Lu Chao.
He set the record in November 2005 at Northwest A & F University in the Shaanxi province of China. It took him 24 hours and 4 minutes to recite the 67,890th decimal place of pi without a mistake.
(Want to try it? Start here.)
It’s a great achievement, but we’d prefer to eat pie than to memorize pi. For March 14th, bakers and mathematicians alike have fun baking pi-themed pies.
If you’ve forgotten high school math, pi is the ratio of the circumference of a circle to its diameter. The number is constant, no matter what the size of the circle.
The pi symbol is the Greek mathematical symbol that represents the ratio.
Because pies are round, it’s particularly fitting to have one today.
We use Pi Day as an excuse to have a different type of pie each year. Almost any pie can be decorated for the occasion, from apple or other fruit (photos #2 and #3) to Key lime to pecan or pumpkin (photo #1).
You have enough lead time to have a Pi Day dessert party. Eight people can share one pie.
For a larger event, invite friends to bring their favorite pies.
If you don’t have time to bake, pick up a pie and the garnishes to create the pi symbol (berries, marzipan, mascarpone, etc.).
Pi Day was founded in 1988 by Larry Shaw, a physicist at the San Francisco Exploratorium. On that first day, both staff and visitors celebrated by marching in a circle, and then eating fruit pie.
On March 12, 2009, the U.S. House of Representatives passed a non-binding resolution (111 H. Res. 224) recognizing March 14, 2009 as National Pi Day.
The tradition expanded across the globe among countries that use the month-day format (i.e., 3.14). Who on this earth doesn’t want a reason to eat pie?
Some bakers make a pastry cut-out of the pi symbol to decorate the top crust (photo #1). Some actually decorate the rim of the pie with the first 31 digits of pi (or however many fit—photo #3). You do it with cookie cutters in the shape of numbers.
If you go for savory rather than sweet, a pizza pie fits right in.
Pepperoni is the perfect medium to create the pi symbol (photo #4). You can add other favorite garnishes around the rim.
We conclude with one of our favorite pie quotes, from Yogi Berra:
“I cut my pie into four pieces. I didn’t think I could eat eight.”