Rank progression of Japanese professional players
While compiling Go4Go database, player rank information is often the most difficult piece of information to verify. A very good resource for Japanese rank progression is online at:
As of September 2015, this page covers 630+ players. There are also links to Nihon and Kansai Kiin's player information pages.
[November 2015] The author of this page has kindly shared his data with Go4Go. As a result, I am able to put the data in database and generate the same information using a computer program. Please follow this link. In the future, Go4Go will expand the database to give similar information on Chinese and Korean players too.