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How FIDE Ratings Work

The FIDE rating is the official number of over-the-board chess: one pool, one algorithm, published monthly. It runs on the classic Elo system — simple enough to compute by hand.

The formula

Before the game, your rating and your opponent's imply an expected score:

E = 1 / (1 + 10^((Ropponent − Ryou) / 400))

Equal ratings give E = 0.50; being 200 points stronger gives about 0.76. After the game your rating moves by K × (S − E), where S is your actual score (1, ½ or 0). Beat expectations and you gain; fall short and you lose the same amount. One special case: any rating gap larger than 400 points counts as exactly 400 (the 400-point rule), so a huge favourite still risks something. Try any pairing in the Elo change calculator.

K-factor: how fast your rating moves

A high K makes new ratings settle quickly; the low K keeps elite ratings stable. This is why a newcomer can gain 150 points in one open while a grandmaster grinds for years over the same distance — the rating goal calculator shows the difference in games.

Getting your first rating

You need rated-tournament games against already-rated opponents: at least 5 of them (poolable across tournaments within 26 months), at least half a point against a rated opponent, and a performance of at least 1400. Since March 2024, 1400 is also the rating floor — FIDE publishes no rating below it. New ratings are then recalculated and published on the first of every month.

Performance rating and titles

Besides your running rating, each event has a tournament performance rating — the level you played at in that one event, computed from your score and your opponents' average rating with the performance rating calculator. Titles are built on it: norm titles like IM and GM require performances of 2450 and 2600 in qualifying events.