JavaScript is not Enabled!
Chess Articles

HOW TO CALCULATE YOUR ELO RATING

Hi everyone, at some point in your chess life you may have wondered or asked yourselves “What is my Elo rating?” or “How is this being calculated, at least for myself?”. You may have responded on this by telling yourselves to simply register or participate in the tournaments sanctioned by the National Chess Federation of the Philippines (NCFP), the governing body for chess in the country. Well, this could be an answer for some, in particular, those who are on the top lists of their amateur class or those entering the threshold of achieving the national master status. For some reason, sometimes even these caliber of players shy away of participating NCFP matches let alone the majority of the chess enthusiasts. Having said this, we should not lose hope especially during this internet era which by just “googling” everything we wanted to know, a tremendous amount of information from different websites competing and rushing to appear. However, the downside is that there are too many information which you would find yourself digging in a vast array of infinite knowledge. For that reason, this article is created. To simply put, at the end of this article you will be able to determine your Elo rating in no time. The method allows considering the level of the player, i.e. you could consider yourself as “beginner” or “master”. Before I share to you the meaty part, allow me to introduce first the source, I mean who invented it to at least pay tribute to his noble deeds and what are the parameters or inputs needed to calculate.

Arpad Elo

The Elo rating system is created for the purpose of determining the relative skill levels of players in games of which this is widely used, such as chess. The name was taken from its creator, Arpad Elo, a Hungarian-born American physics Professor. Apart from being a professor, he was also a master-level chess player who was an active participant of the United States Chess Federation (USCF) from its founding in 1939.

The difference in the Elo rating serves as the determinant of the outcome of the match between the two players. A player with a rating 50 points greater than his opponent is expected to have a score of 57% while a 100-point difference will result with 64%.

A player's Elo rating is represented by a number which increases or decreases based upon the outcome of games between rated players. After every game, the winning player takes points from his opponent. In a series of games between a high-rated player and a low-rated player, the high-rated player is expected to score more wins. If the high-rated player wins, then only a few rating points will be taken from the low-rated player. However, if the lower rated player scores an upset win, many rating points will be transferred. The lower rated player will also gain a few points from the higher rated player in the event of a draw. This means that this rating system is self-correcting. A player whose rating is too low should, in the long run, do better than the rating system predicts, and thus gain rating points until the rating reflects their true playing strength.

Player's Old Rating

This is the rating of a player prior to his tournament. This will come handy if you already knew your rating. However for the unrated, this will require estimation in which the basis would be the other players with known Elo rating.

Opponent’s Rating

As mentioned in the previous outline, this is straightforward if would-be opponents already have their rating. Otherwise, there is a need to make a good estimate based on their previous tournament performance.

Scores - Elo Rating System

In chess, there are only three outcomes in any match. These are win, loss and draw. Each has a corresponding point namely, the “win” is given with one (1) point while the “loss” is zero and the “draw” being half (½) point. In the calculation of Elo rating, similar points are adapted.

Expected Score

The formula to calculate this uses a number, 10 raise to a given power. This power is defined as the ratio of the difference in rating of both players and a constant number, 400.

K Factor

This is where you separate the masters from beginners. This factor is required in the calculation of the “new” rating of the player after the match. K for masters is assigned with a value of 16 while for beginners is 32. Note of the huge difference when a certain player has achieved a master status, his Elo rating climb slower compared to beginners.

Player’s New Ratings

This is defined as the sum of the player’s old rating and the product of the K-factor to the difference of the summation of the scores and expected scores.

Your Elo Rating

To your right is the table that lets you calculate your Elo rating or your friend’s. It allows you to key in five (5) numbers of games at any one-calculation session by which you will be able to determine your rating. You may be wondering now if you have number of games more than five, say nine (9) games. You may have asked yourself how would you go about it. The steps involve two sessions of calculation. Firstly, determine your Elo rating for the first five games. The resulting “new rating” will be used as input for the “players old rating” during the second session of calculation. In this second session, the outcomes of the remaining four (4) matches together with the opponents rating are keyed in. The resulting "Players’ new rating” is your Elo rating after that tournament.

Back to Top

Players Corner

SHARE THIS SITE



CALCULATE YOUR ELO RATING HERE

Player's old rating:

Opponent's Rating Score Expected Score
Sum

K-value (16=Master, 32=Beginner)

Player's new rating:

© Copyright 2014 SJDM WooDPushers. Designed and Powered by Jake Skymel Web Design.