Chess Rating Calculator
FIDE's K-factor slides from 40 to 10.
FIDE's K-factor slides from 40 to 10.
1 for a win, 0.5 for a draw, 0 for a loss.
New rating
1,625
+25.2 from 5 games · performance 1,800
FIDE varies the K-factor by experience: 40 for a player with fewer than 30 rated games, 20 for most established players, and 10 once someone has been rated above 2400. That sliding scale lets new ratings converge quickly while keeping established ones stable. Performance rating answers a different question — what rating would produce this score against these opponents. It is average opponent rating plus a factor from the score percentage, and a single strong tournament can produce a performance rating hundreds of points above the actual one. The expected score is what makes the system work. Beating someone 200 points below you gains almost nothing because you were expected to; losing to them costs a great deal for the same reason.
How the Chess Rating Calculator works
Rating change across a whole tournament by FIDE rules, with the correct K-factor chosen for you and a performance rating alongside. Performance rating answers a different question from the new rating, and both are shown.
Also known as: fide rating change calculator · chess performance rating · what k factor applies to me · how much rating from a tournament
Where to go next
The Chess Rating question rarely arrives on its own. These are the ones that usually come with it:
- Elo Rating Calculator — Zero-sum: what one gains, the other loses.
- Probability Calculator — Two events combined, and the odds over repeated trials.
- Golf Handicap Calculator — Best eight of twenty, but only once you have twenty.
- Percentage Calculator — Every common percentage question in one place.
Frequently asked questions
How does FIDE choose the K-factor?
40 for players with fewer than 30 rated games, 20 for established players, and 10 once a player has been rated 2400 or above at any point. The slide lets new ratings settle fast and old ones stay stable.
What is a performance rating?
The rating that would produce your score against those opponents — average opponent rating plus an adjustment from the score percentage. A strong tournament can produce one hundreds of points above your actual rating.
Why do I gain so little for beating a weaker player?
Because you were expected to. The expected score for a 200-point favourite is about 0.76, so a win only beats expectation by 0.24 and the rating moves accordingly.
How much does one tournament change a rating?
For an established player with K=20, rarely more than 30 to 40 points across a normal event. For a new player at K=40 it can be several times that.
Are online ratings the same as FIDE ratings?
No. Chess.com and Lichess use their own pools, K-factors and in Lichess's case a different system entirely (Glicko-2). Online ratings usually run higher than FIDE for the same strength.
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