International Chess Federation
beta
RATING CALCULATORS
Rating
Change
Initial
Rating
Calculate Rating Change
Help notes:
Rating - Rating of a player.
Rc - Opponent rating.
W - Score.
K val - K is the development coefficient.
K is the development coefficient.
K = 40 for a player new to the rating list until he has completed events with at least 30 games
K = 20 as long as a player's rating remains under 2400.
K = 10 once a player's published rating has reached 2400 and remains at that level subsequently, even if the rating drops below 2400.
K = 40 for all players until their 18th birthday, as long as their rating remains under 2300.
K = 20 for RAPID and BLITZ ratings all players.
Calculate Initial Rating
Help notes:
Rc - Average rating of rated opponents in all tournaments.
W - Total score against rated opponents in all tournaments.
N - Number of games against rated opponents in all tournaments.
Note: If an unrated player scores zero in his first tournament, his score and that of his opponents against him are disregarded.