Born in New York City in an Italian-American family, Cincotti started playing a toy piano at the age of three. While in high school, he regularly performed at clubs throughout Manhattan and performed at the White House. At the 2000 Montreux Jazz Festival, he won an award for a rendition of Dizzy Gillespie's "A Night in Tunisia." In 2002, he reached No. 1 on the Billboard Traditional jazz Charts, the youngest solo artist to do so to date.
Cincotti appeared in a small role in the 2004 Bobby Darin biopic Beyond the Sea and contributed to the film's soundtrack. He also had a small role as the Piano Player in the Hayden Planetariumin Spider-Man 2. His song "December Boys" is featured in the 2007 film December Boys, starring Daniel Radcliffe.
His self-titled debut album is a compilation of traditional jazz songs, while his second album, On the Moon, featured some of the artist's own songs. Combining elements of pop, jazz, funk and, rock, his third studio album, East of Angel Town, features all original works by the artist and was released in 2007 in Europe and in January 2009 in USA.
This project began when Cincotti teamed up with producer David Foster (who signed him to a new contract on his Reprise/Warner Bros.-distributed 143 Records), producer Humberto Gatica, and producer/sound designer Jochem van der Saag.
In 2008, he collaborated with French DJ/producer David Guetta and they appeared together on the finale of Star Academy performing a new version of the song Love Is Gone.
Combining pop, jazz, rock and dance, Cincotti created his fourth studio album, Metropolis, produced by John Fields and released worldwide in the spring of 2012.
In July 2012, Peter and his sister Pia Cincotti wrote and produced an original full length musical entitled "How Deep Is The Ocean?" (music and lyrics by Peter Cincotti, and book by Pia Cincotti) which debuted at The New York Musical Theater Festival (NYMF) to sold out audiences in New York.
In 2013 he participated in the Festival of Sanremo, singing the song with Simona Molinari: La Felicità (The Happiness)