- Pi Day is a special day celebrated on March 14th every year, by math nerds, number lovers and pi(e) enthusiasts around the world.
- March 14th is, numerically, 3.14, which are the first three digits of the mathematical calculation of π, or “pi,” which represents the ratio of a circle’s circumference to its diameter:

- π is the subject of admiration, reverence and even obsession for many people because of its infinite nature; that is, it goes on forever and ever without any known pattern or repetition.
- In addition to “Pi” being pronounced the same as “Pie,” 3.14 backward is also easily read as PIE:
- Pi has been calculated to over 1 trillion digits past the decimal. How many digits do we really need? 3.14159, or 5 digits past the decimal, seems to be enough for most practical purposes, and apparently to accurately calculate the spherical volume of the entire universe, only 39 digits past the decimal are needed (source). But that doesn’t stop people from wanting them all!
- Someone took out a web domain based on the digits of Pi, website here . And apparently, if you can guess the URL (.com/index[?].html) you can see the first million digits of Pi. I couldn’t get it in my first few tries, but let me know if you do! (Update: The oh-so-clever Rarasaur rose to the challenge and found the currently correct link here. However, the website owner apparently changes it frequently because of the unmanageable amount of traffic it receives, so there’s no guarantee the link will stay valid for long!)
- But if that’s not enough for you, you can see the first 10 million digits of Pi here! Such scrolling! So numbers!
- Speaking of Pi-related websites, you can also find your birthday, or any other significant numbers, in Pi here. My birthday is in the first 2000 digits!
- Next year, March 14, 2015 will be “The Pi Day Of Our Lives,” culminating at precisely 9:26:53. Put the numbers all together and you get the first 10 digits of Pi. In 2010, a particularly keen high school student realized this and started a campaign to prepare for it. You can get your own wristband for the cause here, at a cost of $3.14 including shipping.
- In Japan, Pi Day is largely eclipsed by White Day, a semi-holiday which is the response to Valentine’s Day. (In Japan, women give men gifts, mainly baked goods and chocolates, on Valentine’s Day, and the men are supposed to reciprocate on White Day).
- Japan is not without its Pi fans, though. The world record for reciting digits of Pi was held by Japan for 10 years before they were usurped by China. The current record holder for reciting the most digits of Pi accurately is Chao Lu, of China, who recited 67,890 digits in 2005 to take the Guinness World Record. It took Lu 24 hours and 4 minutes. (See the full ranking list here.) There is also a Japanese guy that claims to have recited over 100,000, but his claim is unverified by Guinness.
- One of the greatest minds of all time, Albert Einstein, was born on March 14th.
- In the movie Life of Pi, the mostly-CGI tiger, Richard Parker, was based on a Bengal tiger that calls the Taipei Zoo home. This is a
*little*off topic from the rest of this list, but I mostly just wanted to brag that I met Richard Parker… (see the full post about that adventure here) - Last but probably not least, there’s a chance that Pi may hold the key to more than we could possibly imagine. And by that I mean this equation cannot simply be a coincidence: 3.14159 × 1337% = 42. That is all. Happy Pi Day!

## Bonus!

#### Show off what you’ve learned:

*Find the secret message contained in this blog post!*

(Stumped? Yespleasetellmetheanswer!)

Fantastic primer! I work with a bunch of military brainiacs that make me feel below-average, so I’ve been hearing about Pi Day for a while. But I never saw so many great trivia tidbits put together.

Great, glad you enjoyed it! Now maybe you’ll have some Pi knowledge of your own to share next time around!

I tried to evangelize the Mrs. in the process of telling her about my funny comment. “What’s the big deal with pi?” she asked. Geometry, figuring out the area of circles and spheres… somehow this led to discussing how pi could be used to help determine the blast zone of a tactical nuke in order to minimize collateral damage when developing small-scale weapons… um… I need to think of some better examples.

Dude, you’re going about it all wrong if you want to win your wife over. My husband’s coworker just submitted his marriage registration on Pi Day – he’s a math teacher so he did it for the symbolism. Pi, goes on forever… “like our love…”

OMG. Romantic math teachers? Who knew!

I’m looking at this and trying to figure it out! It’s distracting me from all sorts of other things I’m supposed to be doing!!

Oh no, haha! I guess I’ll have to share the answer later, won’t I? It’s been driving a certain person around here a little crazy, too, and he’s quite upset that I won’t tell him.

Yes, you will! I only had a few minutes at my computer but I was analyzing your sentences and words and looking for patterns and making my brain melt.

I love math but I never knew there is a pi day. 😦 Next year, I’ll copy and paste your blog. 😀 See you next 3.14 😉

Well glad I could introduce you to Pi Day! Next year will be a very special one… 3/14/15! 😀

Thank you very much. Waiting for next year! I’ll celebrate 10 days till 13/14/15 😀

What an awesome post!

I will have to look at this again in a few hours to see if I can figure it out…though by then I am sure someone else will get it 🙂

Thanks, I hope someone gets it! Maybe I should throw in a pie as incentive, hahaha! 😉

Hmmm, leetcode. I will have to think about this. Or could it be that you published your blog 3.14 at 1:59?

Hmmm, leetcode. I will have to think about this. Or, could it be that you published your blog on 3.14 at 1:59?

That is true about the posting date/time, but it’s not the secret. Keep looking!

Got the link, it’s http://3.141592653589793238462643383279502884197169399375105820974944592.com/index3141.html 🙂

This post is great! 😀

Haha, thanks! You’re so clever. I’ll update that point! 😀

My birthday isn’t even in the top 250,000! Unless I just do month-day, 827 is in the first 620 digits. 🙂

Alright, I’m clearly obsessed with every link in this post. I have no idea what the secret message is, though… will there be a reveal at some point? 🙂

If no one figures it out I suppose there will be, however I have faith. You have to think outside the box but if you know what you’re looking for it shouldn’t be that hard to see! 😉