Check out these National Pi Day pizza deals

Pi Day isn't just about showing off how many numbers you have memorized - restaurants from Burger King to California Pizza Kitchen are offering deals and discounts on Thursday, March 14.

Pi Day occurs on March 14, because the date is written as 3.14 in the United States. Pi is the ratio of the circumference of a circle to its diameter, or approximately 3.14 (its exact value is infinite and can't be calculated). March 14 also happens to be Albert Einstein's birthday.

RELATED: What is Pi Day? What to know about the holiday to celebrate math's beloved irrational number

With eating out becoming more of a luxury, restaurants use such deals to help draw customers to fast casual and fast food chains.

Pi Day has also become synonymous with pizza pie (and other round foods) - here are some deals to round out your celebration.

Pizza Hut

From March 12-14, Pizza Hut has been offering a free large one-topping pizza with purchase of a large menu-priced pizza.

7-Eleven

Loyalty members can get any flavor large pizza for $3.14 in 7-Eleven, Speedway and Stripes stores - limited to one transaction, two per day.

BJ's Restaurant & Brewhouse

Dine-in customers at BJ's Restaurant & Brewhouse can get a mini one-topping pizza for $3.14.

Blaze Pizza

Build-your-own-pizza chain Blaze is offering an 11-inch pizza for $3.14 in-store at participating locations.

Burger King

As part of its week of breakfast deals, Burger King is offering a free Hershey's sundae pie with a $3.14 purchase.

California Pizza Kitchen

CPK rewards members can get an Original BBQ chicken, pepperoni, or traditional cheese pizza for $3.14 with a dine-in purchase of $25.

Taco Bell

Get a Taco Bell Mexican Pizza for just $3.14.

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