A record 13 hours of Pi

Remember this number, 3.14159? It's Pi, the natural number that describes the mathematical properties of a circle. Well, the digits for Pi go on and on and on (for infinity actually) and that makes for some fun competitions and great feats of memory. As a matter of fact a 59-year-old Japanese psychiatric counselor, Akira Haraguchi, has recently broken the world record for reciting the digits of Pi from memory. From the time he started at 3.14 to the time he ended 13 hours later he recited 42,195 digits of Pi.

Pi diagram

Can you imagine memorizing that many numbers? Check out the first 10,000 digits of Pi to see how hard it is to remember that many numbers. And if that doesn't wear you out, try for the record by checking out the first 100,000 digits of Pi.

To learn more about the fun aspects of Pi, check out the Exploratorium's Ridiculously Enhanced Pi Page. Every March 14th, international Pi day, in San Francisco the Exploratorium hosts a Pi festival with lots of fun activities, including real pie.

To learn more about human memory, check out the BBC's Human Body and Memory Tests website. You can explore some amazing facts about the human mind but also take a number of surveys to test your own memory.

Your Comments, Thoughts, Questions, Ideas

Anonymous's picture
Anonymous says:

this is absolutely amazing information i couldn't believe a guy could actually do that kind of thing

posted on Thu, 07/14/2005 - 2:10pm
Anonymous's picture
Anonymous says:

I know the last character of pi...\r\nit's...\r\ne\r\nhehe...!

posted on Tue, 03/28/2006 - 5:38pm
bryan kennedy's picture

Har har, very funny.

posted on Tue, 03/28/2006 - 6:17pm
Jessica's picture
Jessica says:

I appreciate that you keep this blog going and allow comments. To me feedback is an interesting part of a blog.

posted on Fri, 07/15/2005 - 7:33pm
me's picture
me says:

hi..i like pi and i think you should post all the numbers of pi. some people found out where pi ends using a super computer.

posted on Thu, 09/29/2005 - 5:12pm
Gene's picture
Gene says:

Can you tell us where you heard that pi had been solved? I just surfed the web, and couldn't find any reference to that. And something like that would be BIG news!

I did, however, discover two things:

a) in 1995, a scientist in Tokyo, Japan calculated pi to over 6.4 billion places.

b) according to the Exploratorium site above, just one billion places of pi would stretch from New York to about the middle of the US. So six billion would stretch from NY to LA, back to NY, back to LA, and still have enoough left over to get down to San Diego to catch a Padres game.

So, I don't think we'll be posting all the numbers of pi any time soon. ;-)

posted on Sun, 10/02/2005 - 9:39pm
Apple Pi's picture
Apple Pi says:

pi does not end........

posted on Fri, 03/17/2006 - 5:12pm
Anonymous's picture
Anonymous says:

what if iwere to change the units used into radian? what would the formulas be then? please explain

posted on Tue, 12/06/2005 - 11:39am
Gene's picture
Gene says:

The formula for pi is always circumference divided by diameter. The units of measure used don't make any difference.

posted on Tue, 12/06/2005 - 2:44pm
green sea floyds's picture
green sea floyds says:

you can't find pi its an irrational number, if it has been solved it's probbably a hoax.

posted on Mon, 10/22/2007 - 7:42am
icee's picture
icee says:

I am 13, and I learned 150 digits of pi in 3 hours, and am able to recite them from memory in about 30 seconds.I am continuously learning more.

posted on Thu, 11/15/2007 - 6:46pm
Anonymous's picture
Anonymous says:


posted on Tue, 01/15/2008 - 7:25pm
Anonymous's picture
Anonymous says:

what kind of a life did he live

posted on Tue, 01/15/2008 - 7:24pm
Domivoi's picture
Domivoi says:

Hey guys, I''m 10 years old with 501 digits of pi! It was easy to memorize. I'm aiming for 601 this year.

posted on Mon, 03/10/2008 - 7:11pm
Moo Moo's picture
Moo Moo says:

Didn't you ever think of putting it down here?

posted on Sun, 03/23/2008 - 5:33pm
zak's picture
zak says:

Interesting article, i have bookmarked your blog for future referrence

posted on Thu, 04/09/2009 - 2:47pm
CANSTRICT's picture

hey guys, I'm 16 years old and I've memorized pi to about 2130 places. The trick is memorize sequences of numbers and then string them together. My goal is 10000 places by the time I'm out of high school. I'll tell you how it goes:)

posted on Sat, 06/27/2009 - 3:23pm
HAHAH Geeee Geeee flkjsdklj's picture
HAHAH Geeee Geeee flkjsdklj says:

WOW I feel dumb when I look at the equations for PI π

posted on Tue, 03/09/2010 - 12:03pm

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