Born in Laitila, Finland, Kari started studying classical piano at the age of 8. At the age of 12, he got his first guitar, and since then started to concentrate on playing guitar instead of piano. Kari was autodidact until the age of 23, when he entered in Pop/Jazz Conservatory music school in Helsinki, Finland. After graduating from music school, Kari continued on a degree program of pop/jazz music pedagogue in Stadia, Helsinki, Finland. In Stadia Kari studied with a well-known Finnish jazz guitar player Pekka Luukka.

In 2003 Kari moved to Belgium and studied jazz guitar with famous Belgium Jazz players Peter Hertmans and Philip Catherine. 2006 Kari graduated cum laude from royal conservatory of Gent as a master of jazz music. Kari has also followed master classes for example with Jim Hall, Ben Monder and Michael Brecker.

Besides of his commercial music works in Finland, Kari has worked with many top Finnish jazz musicians, for example Lasse Lindgren, Ville Herrala, Ari Jokelainen, Esa Pethman, Toni Porthen, Ulf Krokfors and Ville Pynssi to name a few. In Belgium he has played commercial music works with top names, such as Lee Towers and has performed for example in Paris olympia, France.

In Belgium Kari has played jazz with Geraardsbergen 86 big band, and Gent Conservatory big band, both led by a famous Belgium trombone player Marc Godfroid. He has also had opportunity to work as leader or sideman in Belgium with Hans Van Oost, Kris Duerinckx, Bart Van Caneghem, Mark Godfroid and Fredrik Heirman with whom he was accompanying in Erasmus Jazzprize Competition 2004 in Rotterdam, Netherlands resulting 2nd. Kari has also performed in Denmark, France, Switzeland, Italy and the United States in different occasions. Kari has his own Kari Antila Trio which is active both in Finland and in Belgium performing his original compositions and jazz standards. Kari has also taught many years in different music schools in Finland and participated as jury faculty in Turku Conservatory, Finland.