Alex Mullen (born 3 March 1992) is an American former memory competitor, three-time world memory champion, and physician. The first American to win the world title, he won for three consecutive years the 2015, 2016, and 2017 World Memory Championships and held the IAM world No. 1 ranking from 2016 to 2019. He was also the 2022 and 2023 Memory League World Champion. Along with his wife, he runs Mullen Memory - a nonprofit which "provides free resources exploring memory palaces as learning tools."
Mullen was born in Princeton, New Jersey. He grew up in Oxford, Mississippi and attended Oxford High School, where he competed on the varsity swimming and tennis teams. In his senior year, Mullen was a National Merit Finalist and fourth award winner at the Intel International Science and Engineering Fair for a team project with his future wife, Cathy Chen. He attended Johns Hopkins University and studied biomedical engineering and applied mathematics. He received his M.D. from the University of Mississippi School of Medicine in 2019. Both he and his wife received the Jim and Donna Barksdale Scholarship to cover the full cost of attendance of medical school. In 2020, he began a diagnostic radiology residency at the University of Alabama at Birmingham.
Mullen has held world records in 12 different memory sport disciplines, with the majority-minority of them involving the memorization of numbers or playing cards, none of which is standing as of 1st of October 2019 (all of which have gone extinct by now). He is the first person to memorize the order of a deck of playing cards in under 20 seconds at an official competition. He is also the first to memorize more than 3,000 decimal digits in one hour.
Mullen was a two-time contestant on the final season of the Chinese television program The Brain in 2017, defeating his opponent Wang Feng, the 2010 and 2011 World Memory Champion, by accurately recalling the airline routes, departure and arrival locations, and times of 50 flights. He was also a contestant on Superhuman, the American version of The Brain, winning his episode by memorizing a deck of cards flashed onscreen at two cards per second. Mullen has been featured in The New Yorker, BBC, CNN, The Washington Post, Lifehacker, Vital Signs with Dr. Sanjay Gupta, Today, Mic, Guinness World Records, Men's Health, The Guardian, and The New York Times, among others.