Kobayashi began his career in letters at Musashino Art University in Tokyo, where he studied from 1979 to 1983. His first work experience in type design was at Sha-Ken Co., Ltd., a manufacturer of phototypesetting machines. After working for Sha-Ken for several years, Kobayashi left in the late 1980s and traveled to London to study English and calligraphy. A year later, he returned to Japan to design type for Jiyu-Kobo. From here, Kobayashi went to TypeBank where he created 17 Latin alphabets to accompany the foundry's Japanese fonts. From 1997 to the first part of this century, he worked as a freelance type designer and teacher of lettering (both Japanese and Western alphabets).
In the spring of 2001, Kobayashi was named type director of Linotype. For the next several years, he worked with Hermann Zapf and Adrian Frutiger in reinterpreting their classic typefaces, including the Palatino® Nova, Optima® Nova, Avenir® Next, Frutiger® Serif and Neue Frutiger designs.