To some people, Pi Day is about mathematics. To others, it’s an excuse to eat pizza.
Either way, there will be celebrations on Friday, March 14.
Pi is the ratio of a circle’s circumference to its diameter, named after a Greek letter. It’s a constant number with an infinite number of digits, as explained by the U.S. Census Bureau.
Pi Day falls on March 14 because the first three digits of Pi are 3.14.
NASA’s Jet Propulsion Laboratory in La Cañada Flintridge marks Pi Day online with classroom activities and a Pi Day Challenge.
But at some point, people began associating pi with eating round foods, mostly pizza but sometimes fruit pies.
Pi may be never-ending, but the deals it inspires are short-lived. Most of the promotions described below are only good on March 14.
7-Eleven: Loyalty members can get whole pizzas for $3.14. 7-eleven.com
BJ’s Restaurants & Brewhouse: Dine-in guests can buy one Pizookie and get a second for $3.14. The offer is good for all flavors but can’t be combined with other Pizookie deals. bjsrestaurants.com
Blaze Pizza: Customers can buy one 11-inch pizza and get a second of equal or lesser value for $3.14. The offer is for in-restaurant purchases only. blazepizza.com
North Italia: This Phoenix-based chain comes out with new pizzas that are exclusive to their markets on Pi Day. California’s pizza is Costa Brava, made with clams, crab, crispy pancetta, blistered tomato, crushed chili and lemon. It will be available March 14 through April 11. northitalia.com
Mountain Mike’s Pizza: Customers can get a free mini pizza with the purchase of a 20-ounce bottled beverage. mountainmikespizza.com
Pitfire Pizza Kitchen: Mini Margherita Pizzas will cost $3.14 with any purchase until 3:14 p.m. At that time, the first 314 guests at all locations will qualify to win gift cards and merchandise. pitfirepizza.com
Polly’s Pies: The casual chain will be baking the pi symbol in its apple pie crust for the occasion. Dine-in guests who order an entrée will get a free slice of pie, and dine-in rewards members can get a free slice of pie without making a purchase. pollyspies.com
Pop Pie Co.: This San Diego-based chain will mark Pi Day with three pie collaborations. They are Smoked Pulled Pork Mac & Cheese Pie with Heritage Barbecue; Dirty Flattop Cheeseburger Pie, with The Friendly SD; and Banh Mi Pie with Grains Cafe. poppieco.com
Round Table Pizza: Royal Rewards members can get a personal cheese pizza for $3.14 with the purchase of a large or XL pizza on Pi Day. New members must sign up before March 14. roundtablepizza.com