Kato became a professional in 1990, and in the same year was promoted to 2 dan. In 1996, he had already reached 6 dan, and became 9 dan in 2011.
Kato became proficient in 1990, and at the same time achieved the rank of 2 dan. By 1996, he had advanced to 6 dan, and was subsequently elevated to 9 dan in 2011.