1. What is the Elo Win Probability?

The Elo rating system is a method for calculating the relative skill levels of players in competitor-versus-competitor games. The win probability formula estimates the expected outcome between two players based on their Elo ratings.

2. How Does the Calculator Work?

The calculator uses the Elo win probability formula:

Where:

• \( P \) — Probability of winning (0 to 1)
• \( R \) — Your Elo rating
• \( R_{opp} \) — Opponent's Elo rating

Explanation: The formula calculates the expected score (win probability) based on the rating difference between two players. A player with a higher rating is more likely to win.

3. Importance of Elo Rating

Details: The Elo system is widely used in chess and other competitive games to rank players and predict match outcomes. Understanding win probabilities helps in strategy development and match preparation.

4. Using the Calculator

Tips: Enter both players' Elo ratings (must be ≥ 0). The calculator will show the probability of the first player winning against the second player.

5. Frequently Asked Questions (FAQ)

Q1: What does a 50% probability mean?
A: A 50% win probability indicates that both players have equal Elo ratings and are equally likely to win.

Q2: How accurate are these predictions?
A: The predictions are statistically accurate for large numbers of games, but individual matches can have different outcomes.

Q3: What's the significance of the 400 in the formula?
A: The 400 determines how quickly win probability changes with rating difference. A 400-point difference means the higher-rated player is 10 times more likely to win.

Q4: Can this be used for team ratings?
A: Yes, the Elo system can be adapted for team vs team matchups by using average team ratings.

Q5: How are ratings updated after a match?
A: The winner gains points based on the probability (more points for upset wins), while the loser loses the same amount.