Ergosoft Corporation (株式会社エルゴソフト, Kabushiki-gaisha Ergosoft) was a software development company that served as a subsidiary for Koei in 1993. Originally established on January 27, 1984 at Yokohama, it developed multi-platform word processors like EGWORD and EGBRIDGE before focusing more on internet usage and data management in order to keep up with the growing competition. In 2001, many of its products were optimized for the Mac OS X which had been the prevalent operating system at the time.
Despite its change in direction, Ergosoft received the Good Design Award in 2006 for their contribution in developing the Japanese input system with EGWORD. The company officially dissolved in March 2009 and its assets were liquified afterwards. Many of its former engineers are now affiliated with Monokakido, a group that makes dictionary apps for Apple devices.