The Pi Matrix Challenge is also called the 'Everest of Memory Tests'. It requires the memorizer not only to know the actual order of the first 10,000 digits of pi, but also to know the digits in the correct order from anywhere in the sequence. It is a bit like learning a book, and then being given a sequence of just a couple of words from it, and asked to remember the words that appear on either side.

The first 10,000 digits of pi are divided into 2000 5-digit blocks. The testers call out one of these 5-digit sequences, and the candidate must say the 5-digt sequence before - and the 5-digit sequence after the choosen sequence. This happens 50 times. The record is for the time taken to recall the event, with no errors.

Feel free to get the first 10 000 digits of pi in this division, with collision-marks, a list with one thousand digits per page and a list of all the collisions.


The rules have been worked out by Grandmaster Kevin Horsley. He has made an introduction video as well.

Pi Matrix Trainer

We have created a tool which helps you check your knowledge of the Pi Matrix. Try our Pi Matrix Trainer.

Hall of fame

1. Martin Nilsson (Sweden) 5 October 2019. Time 14min 33sec.

2. Kevin Horsley (South Africa) 14 March 2013. Time 16min 38sec.

3. Lars Christiansen (Denmark) 30 March 2019. Time 16min 50 sec.

4. Mark Nissen (Denmark) 29 March 2019. Time 16min 51sec.

5. Mats Bergsten (Sweden) 12 Feb 2008. Time 17min 39sec.

6. Jan Harms (Germany) 27 July 2007. Time 20min 30sec.

7. Philip Bond (U.K) 28 June 2004. Time 29min 51sec.

Pi Space Matrix Challenge

Rules: The first 100,000 digits of Pi are divided into 1,000 pages, containing 10 rows with 9 digits and 1 row with 10 digits each. The testers call out one of these 9- or 10-digit sequences, and the candidate must reply with the 9- or 10-digit numbers on either side of the number chosen. This happens 50 times. Jonas von Essen from Sweden was the first to pass this test on 10 March 2020 in a time of 33 minutes. You can read more about the event. Try our Pi Space Matrix Trainer as well.