He started cubing at the age of 9, and began speedcubing in 2002 when he was 12. Using CFOP, he achieved his initial goal of averaging under 20 seconds in about a year. He attended the World Rubik's Games Championship 2003 competing in 3x3, 4x4, and 5x5 events, and was one of just two cubers who completed a successful solve in the 3x3 Blindfolded. Although competing as a Japanese national, he was living in Southern California.
Between 2004 and 2005 he gained multiple world records in 3x3, 2x2, 3x3 One-Handed, and 3x3 Blindfolded. At the inaugural US Nationals 2004 he won the 3x3 and the 3x3 Blindfolded events. At the Caltech Winter competition (2004 October 17) he became the first person to achieve an official 3×3 solve under 15 seconds (14.76 secs). At the Rubik's World Championship 2005 he finished in third place for the 3x3 event, and in second place for 3x3 One-Handed. He finished in second place for 3x3 Blindfolded at the World Rubik's Cube Championship 2007.
His Cubefreak website contained all of his CFOP algorithms, as well as descriptions of miscellaneous techniques, a guide for blindfold cubing, and speedcubing videos. He frequented the JSCC (Japan Speed Cubing Club) forum, and adopted the Japanese numbering system used by Japanese cubers for OLL/PLL, and helped to introduce the system for numbering OLLs from 1 through 57 which is now standard in the western cubing world. Similarly he helped to introduce the Japanese system of denoting wide turns on big cubes with the letter w. (Katsuyuki Konishi's Japanese-language website which was a useful resource for English speakers also introduced these notations).
He was also the originator of the MGLS method for solving the final F2L slot while simultaneously orienting the last layer.
He graduated from Princeton University (B.A. in Mathematics) in 2012. He became a math PhD student at Stanford University "thinking about geometric representation theory". In 2017 he became Assistant Professor in the Columbia University mathematics department.