# Chess Ratings - How They Work

• erik
• | Aug 23, 2007
• | 189725 views
• | 512 comments

Like it or not, we ALL have a chess rating. You may not care at all about your rating, or you may be whining every time it goes down in the slightest. You might be someone who plays a game a year, or someone who plays 1,000 a day. Still, there is a number out there that represents how well you play chess. Well, that's the theory, anyway.

To understand chess ratings you have to understand two things: #1 - that you have a TRUE rating that perfectly represents your strength of play, and #2 - that that TRUE rating will never be known and so we have to use statistics to get as close as possible to the truth. I'm writing this article in response to many people who ask about ratings and need a simple explanation of how they work. (I only know about all this because of a recent super-in-depth statistics course I took and my research in building Chess.com!)

There are two main rating systems, and each one has its merits.

The Elo System (used by the United States Chess Federation, FIDE, and many other online chess sites) is popular for two reason - it has been around for a long time, and it is simple. The idea is this: given two chess players of different strengths, we should be able to calculate the % chance that the better player will win the game. For example, Garry Kasparov has ~100% chance of beating my 4-year-old daughter. But he may only have a ~60% chance of beating another Grandmaster. So when playing that other Grandmaster, if he wins 6 games out of 10, his rating would stay the same. If he won 7 or more, it would go up, and 5 of less, his rating would go down. Basically, the wider the spread of the ratings, the higher percentage of games the higher rated player is expected to win. So to calculate a person's rating after playing a few games you calculate the average ratings of his opponents, and then how many games he was expected to win, and then plug it into a formula that spits out the new rating. Simple enough. Well, it turns out, that is maybe TOO simple.

I wish there was some simple analogy to explain all this, but there isn't. It all comes back to this: you have a theoretically exact chess rating at any given moment, but we don't know what that is and so we have to use math to estimate what it is. There are really smart people out there who work on this stuff for a living, and at the end of it all we get to put their proven methods into our code so that we can all enjoy knowing what little numbers next to our name we deserve.

If you want to read more, check out these articles (WARNING - SEVERE NERD CONTENT AHEAD):

• 4 years ago

I am playing a game on here and my opponent refuses to make a move. It looks as if I have got very much the stronger position.

My opponent doesn't want to lose any of her rating so she says she will simply let the game time out instead of resigning or making moves. If she moves I will be able to checkmate her very soon.

How will my rating be affected if she lets the game time out?

Will I gain any points?

How will her rating be affected. Will she lose any points if she doesn't move and simply allows the game to time out?

How does the rating system work in a case like this?

(In her position she ought to resign because I will probably have her in checkmate in about 5 or 6 moves otherwise.)

• 4 years ago

:)

• 4 years ago

You want to quit because you're losing and don't want your rating to drop?!
That's not very sporting of you.

"Anyway, I've played one French defense, and to my disappointment white played the exchange. I opened with a French again just recently, and white, on his third move took on d5 again! Uhhgg. I asked in another forum if I could abort, and it seems like I can not, but 2 people answered that I should resign as it would NOT be rated since only 3 moves were made. (2 by black, 3 by white.) My time is running out, and I will play if I need to. But if I let the time run out, or if I resign and the game is not counted, I would opt for that and start a new game. I'm glad I was referred to this specific forum, where I can hopefully get a definitive answer to my "abort" question in some "general issues forum". Thank you in advance for your answer."

• 4 years ago
I just joined chess.com. I do not consider myself a beginner but not sure how i fit. Any suggestions who i can play? Are all games timed?
• 4 years ago

thanks for good clear concise explanation... nice to know that whether its in-depth nerd material or simple explanation, doesn't change the fact that overall i still suck at chess compared to most other players- still love to play it though

• 4 years ago

Thanks much for the clarification. A lot of us have been wondering and have apparently missed wherever that was announced.

• 4 years ago

All new members now start off as "unrated" although they are still technically rated 1200.  As soon as they finish their first rated game, their ratings will update.

The same goes for current members who show "unrated".  When they finish their next rated game, their ratings will display the actual number.  There's no difference in playing an "unrated" player as a member who's ratings are visible.

• 4 years ago

How do I change my stats to a rated player instad of unrated player

• 4 years ago

I am playing an "unrated" opponent but the "details" says it

is in fact a "rated" game. How is my rating affected if I win

or lose?  Thanks all you chess afficianados!

marty

• 4 years ago

What are your opponents' ratings?

• 4 years ago

i play many games

and i most of that games win

of 16 games i win 14

but rating isnt higher when i win

rating is always 1170

or i win or lose rating is 1170!!!!!!!

what i must do

i play tournament

and rating is 1000-1170

maybe for that rating is always 1170

pls help?

• 4 years ago
Hi hgreen! Yes ,you get rated when your opponent's time run out!!!
• 4 years ago

Hi! I am new here and I have played only a few games (6 completed) on this site. Otherwise I have been playing chess for seemingly a million years. Anyway, I've played one French defense, and to my disappointment white played the exchange. I opened with a French again just recently, and white, on his third move took on d5 again! Uhhgg. I asked in another forum if I could abort, and it seems like I can not, but 2 people answered that I should resign as it would NOT be rated since only 3 moves were made. (2 by black, 3 by white.) My time is running out, and I will play if I need to. But if I let the time run out, or if I resign and the game is not counted, I would opt for that and start a new game. I'm glad I was referred to this specific forum, where I can hopefully get a definitive answer to my "abort" question in some "general issues forum". Thank you in advance for your answer.

• 4 years ago

What happens to the rating if you get checkmated on move three?

• 4 years ago

ROY777, if that would be the case then my rating would be 0! I know I am not an experienced or a good player but I would still like to think I'm not that bad...

• 4 years ago

@ROY777 -ROTFL!

• 4 years ago

I have a simple equation for ratings.

Take the number of games being played.Divide by 3.5%....Add the year that you were born. Subtract 10% of net income, multiply by number of times you have had a flat tire in the pouring rain,and THAT,my friends,is your chess rating.

• 4 years ago

I'm sorry but you are wrong there Rafchess! If the number of moves is too small and you win thanks to timeout then you won't get any points and same if the opponent won't make a move at all.

• 4 years ago

Hi, G Raymond ! If the opponent resigns you get point !!

Hi, mufid30 ! When you win a game any way,you get point!!

• 5 years ago

Thank you for your explanation. Now...how do chess ratings work?