Win Percentage Calculator + Online Solver With Free Steps

The Win Percentage Calculator is an online tool that helps find players’ win rates using the Elo ratings. The ELO ratings define how much skilled a player is in a game.

The calculator simply returns the percentage that describes the chance of winning for one player over the other.

What Is a Win Percentage Calculator?

A Win Percentage Calculator is an online tool that can be used to quickly calculate the win percentage of the players of any game.

There are plenty of sports that use the previous ratings of the player or team to predict their win or loss in the next match. It helps sports analysts and coaches to analyze any team’s performance and determine the challenges they may face.

ELO is another rating used primarily on video games and physical sports. Instead of performing any calculations for the predictions, you can directly insert the rating of players in the Win Percentage Calculator to find the most accurate predictions.

To use this calculator, you simply need a good internet connection and a browser where you can access it. Therefore, it completely relieves you from going through any downloading, installation, and sign-up process. 

It is a powerful tool for players, teams, and supporters to determine the win chances of their team before the start of the competition. Please read the following sections to learn how to use the calculator and its mechanism.

How To Use the Win Percentage Calculator?

You can use the Win Percentage Calculator by entering the rating for each player in their respective spaces. It can find the win percentage for only those games with two opponents.

You can easily comprehend the calculator as it consists of only two input fields and a click-button for gathering results. The instructions to correctly use the calculator are given as follows.

Step 1

Insert the ELO rating for the first player in the box having the label ‘Player 1.’

Step 2

Similarly, put the ELO rating of the second player in the ‘Player 2box.

Step 3

After inserting the input, press the ‘Submit’ button. It will display the numerical value of the win percentage of the first player over the second player.

Hence put the rating of the target player for which you want to find the win percentage in the first place.

How Does the Win Percentage Calculator Work?

The win percentage calculator works by finding the win probability of players according to their ELO rating. It always displays the win percentage of the first player, “Player 1,” on the calculator prompter.

The player with a higher ELO rating has a higher win probability as compared to the player with a lower ELO rating. The working of this calculator will be cleared when there is an understanding of the ELO rating system.

What Is the Elo Rating Algorithm?

The ELO rating algorithm is a system to determine the relative skill levels of players in zero-sum two-player games. This rating algorithm is commonly used in many competitive games to rank the players.

Hungarian-American physics professor Arpad Elo introduced the ELO rating system. Hence this ranking system was named after its creator.

The ELO algorithm relates the players’ skill sets in zero-sum games like chess. This algorithm is based on the following three assumptions:

  • The mean performance of both players changes slowly.
  • The performance of the players is considered a random variable.
  • The performance follows a gaussian probability distribution.

This ranking system is widely followed by online chess websites, national chess federations, and also by FIDE, which is the organization of international chess competitions to rank chess players all over the world.

However, it is not only confined to the games of chess only. It is also used in other games as well, such as basketball, football, baseball, and scrabble.

Performance in the ELO System

The players’ performance is not measured. Instead, it is measured in relative terms. It is deduced from wins, losses, draws against the opponent player, and the opponent’s ELO rating.

The winning player gains the points from the losing player, but the amount of the accumulated points depends on the ELO rating of the two players. 

If the player with a high ELO rating wins, fewer points are taken from the player with a low ELO rating. If the low-ranked player wins the game, more issues are taken from the high-ranked opponent.

However, if the game ended in a draw, the player with a low ELO rating gains few points.

When the ELO algorithm is explained mathematically, it assumes that a player’s performance is a random variable. This random variable follows a gaussian distribution; therefore, the mean value of the performance would remain constant.

The win probabilities or expected scores of the players are found through the difference in the ELO rating of both players. If player 1 has the rating of $R_a$ and player 2 has $R_b$, then the expected scores or winning probabilities of both players are given by:

\[E_1 = \frac{1}{1 + 10^\frac{R_b – R_a}{400}}\]

\[E_2 = \frac{1}{1 + 10^\frac{R_a – R_b}{400}}\]

f there is a difference of 100 ELO rating points between the two players. The winning probability of the high-ranked player is 64 percent, and if the difference is 200 points, then the winning probability becomes 75 percent.

This calculator also finds the winning percentage of players by using the above formulae for the given ELO ratings.

The above formulae provide the expected scores; however, after the game ends, the player’s actual score may differ, which can affect his ELO rating. Therefore the ELO rating must be updated using the actual scores after the game finishes.

The ELO algorithm revises the expected scores by a linear adjustment proportional to the number of players who over-performed or under-performed.

If a player has the expected score of $E_a$, but his actual score is $S_a$, then his ELO rating is updated through the following formula:

\[R_a’ = R_a + K (S_a – E_a)\]

Where ‘K’ is the factor for maximum possible adjustment in one game. Its value is ‘K=16’ for professional players and ‘K=32’ for beginner players.

Solved Examples

Let’s solve some problems using the Win Percentage Calculator.

Example 1

Chris and George are top-rated players of a PC game. They decided to play a one-on-one match to find who was the best player. Based on their previous performance, their ELO ratings are given below.

Chris = 1328 points

 George = 1134 points

Determine the win percentage of Chris over George.


The calculator expresses the following solution to the problem.


The calculator gives the decimal approximation for the win percentage.

Win Percentage = 75.33

The above result means that Chris has a 75% chance of winning the match.

Example 2

Twelve teams participated in a football tournament and played matches in two pools. Team ‘The Hawks’ from the first pool qualified for the final with 12 points, whereas the team ‘Pacers’ from the second pool qualified with 18 points.

How many chances are there that team ‘The Hawks’ will win the final match of the tournament?



The win percentage is given as:

Win Percentage = 49.13

So there is a 49% chance that team ‘The Hawks’ can win the tournament.

Math Calculators List

5/5 - (5 votes)