He was born in 1953 in Konin and graduated from law at Adam Mickiewicz University in Poznań. He has played the piano since childhood (as a student, he wrote the anthem of I Liceum Ogólnokształcące [Secondary School No. 1] in Konin, which he attended); however, it is the traineeship in the avant-garde Teatr Laboratorium of Jerzy Grotowski that he deems a breakthrough in his career. In the late 1970s, during the cooperation with Teatr Ósmego Dnia in Poznań, he was a co-founder of the famous Orkiestra Ósmego Dnia. For 10 years (1978-1988), he also cooperated with Teatr Polski in Poznań.
In 1989, Jan A.P. Kaczmarek moved to Los Angeles, where he started cooperating with leading American theatres. Three years later he was granted the prestigious Drama Desk Award, given by theatre critics to the author of the best soundtrack of the year (he was recognized for the music to ’Tis Pity She’s a Whore shown as part of The New York Shakespeare Festival). In the early 1990s, Kaczmarek started to be successful on the international scene as well. His soundtrack to Total Eclipse (1995) by Agnieszka Holland, starring Leonardo DiCaprio, got a lot of publicity. His position as one of the best film music authors was reinforced with, among other things, Washington Square (1997), The Third Miracle (1999), Lost Souls (2000) and Unfaithful (2002). Jan A.P. Kaczmarek has also composed for Polish authors; he is the author of the soundtrack to Quo Vadis (2001), one of the most commercially successful Polish films after 1989 (over 4 million viewers in cinemas).
The most famous soundtrack by Jan A.P. Kaczmarek is that to Finding Neverland (2004) starring Johnny Depp and Kate Winslet. In the race for this job, Kaczmarek beat, among others, James Horner, author of the soundtrack to Titanic. For Finding Neverland, the Polish compositor was awarded Oscar; he was also nominated for the Golden Globe, the Golden Satellite, and the BAFTA award. As an Oscar winner, Kaczmarek composed music for many Hollywood productions, e.g. Evening starring Meryl Streep and Glenn Close, The Encounter starring Richard Jenkins, City Island starring Andy Garcia, or Get Low starring Bill Murray and Robert Duvall. Important titles in the work of Jan A.P. Kaczmarek also include Joanna by Aneta Kopacz, which was nominated for Oscar for the best short documentary in 2015.
Apart from the compositions for the cinema and the theatre, the founder of the Transatlantyk Festival also wrote Cantata On Freedom for the celebrations of the 25th anniversary of Solidarność in Gdańsk, Oratorio 1956 for the 50th anniversary of the Poznań 1956 protests, or Universa. The Open Opera for the 650th anniversary of the Jagiellonian University. In 2011, in the Warsaw Philharmonic, his Jankiel’s Concert for three cimbaloms and the orchestra was premiered; the piece was written for the 200th anniversary of the events described in Pan Tadeusz by Adam Mickiewicz. In the same year, his composition titled Fanfares for the A2 was premiered at the opening of the Świecko-Nowy Tomyśl section of the A2 motorway.
In 2004, Jan A.P. Kaczmarek founded Instytut Rozbitek, which conducts educational and artistic activities. Since 2011, as an artist and the director, he manages the international festival of film, music, and ideas called Transatlantyk. "Why Transatlantyk? By definition, it is supposed to be an intellectual and artistic journey, a tool for travelling," he said in an interview with Tomasz Raczek.
He was awarded Gloria Artis Gold Medal for Merits for Culture (2006) and Order of Polonia Restituta for great services rendered in the field of art and successes in promoting Polish culture (2015).