A graduate of Columbia University and the Mannes College of Music, Aaron Dai began studying piano at the age of five and went on to win the UNICEF Youth Concerts Competition three times by the age of fifteen. As a soloist and collaborative pianist, he has performed around the country and abroad, in New York venues such as Carnegie Hall, Steinway Hall, Symphony Space, and The Town Hall, and cities including Dublin, London, Los Angeles, Mexico City, and San Francisco. Aaron studied with Rachael M. Perez Hayes and Denise Kahn. Other studies include accompaniment and collaborative piano with Marshall Williamson (Juilliard).

Aaron's venture into serious composition began at the University of Pennsylvania under the auspices of George Crumb, and he has since worked with composers Thomas Addison and Rudolph Palmer. His The Night Before Christmas for Narrator and Orchestra has been performed internationally and by actors such as Richard Kind (2006), Ana Gasteyer (2007), David Hyde Pierce (2008), Charles Busch (2009), Andrea Martin (2010), Rachel Dratch (2011), Mo Rocca (2012), Victor Garber (2013), BD Wong (2014), Seth Rudetsky (2015), Caroline Rhea (2016), Judy Gold (2017), Annie Golden (2018), Mario Cantone (2019), John Lithgow (2020), Christian Coulson (2021), Eve Plumb (2022), and Bellamy Young (2023). He has a history of fruitful collaboration with artists in other fields, including the late abstract painter Louise Fishman, poet Eileen Myles, and choreographer Kevin Hill. For his fifteen-minute miniature opera Hamlet, he collaborated with Pulitzer-nominated playwright Jon Marans, and the opera premiered in New York City with actor Darius de Haas in the title role. His symphonic poem The Whydah Returns was added to the archives of the Whydah Museum in Provincetown, Massachusetts, and To a Ten-Year-Old—written in commemoration of the tenth anniversary of 9/11—was incorporated into the aural archives of the National September 11 Memorial Museum. The commissioned choral work You Yourself Must Change It (text by poet Adrienne Rich) premiered in The Town Hall in New York City and aired nationally on Sirius XM Satellite Radio for two months. Aaron is a four-time recipient of the ASCAP Plus Award, Concert Music Division.

A former clarinetist, oboist, and bassoonist, Aaron is now a staff pianist at the Mannes School of Music and the pianist for the New York City Gay Men's Chorus. He lives and teaches in New York City.