Elo Rating Calculator
Calculate the expected rating change when playing against another player.
Win
+0
Draw
0
Loss
-0
How does the Elo Calculation Work?
The Elo rating system calculates the expected score based on the difference between the two ratings. The formula for the expected score of Player A is:
Expected Score = 1 / (1 + 10((Rating B - Rating A) / 400))
After the game, the actual rating change is determined by multiplying the K-Factor by the difference between the actual score and the expected score:
New Rating = Old Rating + K-Factor × (Actual Score - Expected Score)
- Actual Score: Win = 1, Draw = 0.5, Loss = 0.
- K-Factor: Determines how much a rating can change. A higher K-Factor (like 40 for new players) means more volatile rating changes, while a lower K-Factor (like 10 for masters) makes ratings more stable.
Note: Platforms like Chess.com use the Glicko rating system (which includes a Rating Deviation variable), rather than the standard Elo system with fixed K-factors used by FIDE. Therefore, calculations here (Standard Elo) may slightly differ from actual points awarded on those platforms.