After having studied piano with Matti Laukkanen for four years (1989–1993) at Jyväskylä Institute of Music, Ikonen continued his studies 1994 in piano and later in composition at the Jazz Music Department of Sibelius Academy, with such teachers as Jarmo Savolainen, Jukkis Uotila, Anders Jormin, Maria Schneider, Mike Gibbs, Sonny Heinilä and Olli Kortekangas.
[2] In addition to many small jazz groups, Ikonen has composed music to European Saxophone Ensemble, UMO Jazz Orchestra, The Guards Brass Septet, Jyväskylä Big Band, Tanguedia Quintet, Quinteto Otra Vez and Uusinta!-chamber orchestra.
Ikonen has worked with Louis Sclavis, Lee Konitz, Ingrid Jensen, Bob Moses, Stan Sultzman, Vincent Courtois, Mathias Eick, UMO, Juhani Aaltonen, Eero Koivistoinen, and Otto Donner.
[4] Kari Ikonen Trio Kari Ikonen Kari Ikonen & Karikko Trio Toffa Quartet Ajaton Orchestra Nazionale della Luna Ahava Slo Motive Gnomus Lang & Luolajan-Mikkola Markus Holkko Mr Fonebone Otto Donner Quartet Coyote UMO Jazz Orchestra Quinteto ¡Otra Vez!
& La Nueva Orquesta de Cuerdas Awards and honors Grants Numerous smaller grants from Finnish Culture Foundation, The Finnish Arts Council, MES, ESEK, LUSES, Georg Malmstén Foundation and others.