Paying members can see a small graph icon next to a BKR value on many pages (Main page, game pages, Ratings page etc.). Clicking this image will generate and display a graph of BKR history of the selected player and game type, so it can be used to analyze the changes of BKR value since the first finished rated game of this type.
(hide) If you want to play a game with an opponent of a similar level, you can define a required BKR range for a new game invitation. Then nobody with a BKR outside this range will be able to see/accept it. (Katechka) (show all tips)