It's based on the Glicko system-you gain points when you win, lose when you lose. The exact amount of points depends on the difference in points between you and your opponent, as well as how many games each of you has played recently (rating accuracy).
You can check out the math here.
I would recommend that you read through kurtgodden's very informative chess.com article. His article is in English and shows you how you can do the calculations without majoring in Math. 
Thanks 4 the info...
Means that if the player always win all the games.. the static point increase 100+ , If the player lose after win much game the point can be - 200 . fuhhh...
So the conclution.. don't resign until match finish..? or it any posible situation u have to resign the match?
There's no difference in point loss between checkmate and resignation.
Where did you get the idea that resigning weighs differently from being checkmated or losing on time?
There is different point if u resign.. before checkmate. chess.com can u explain..
yes, if you resign before making 5 moves, there will be no rating change for resigning.
however, resigning to avoid a loss is poor sportsmanship. play to win, attempt to swindle your opponent if you make an error in the opening. learn by trying to fnd ways to win regardless of the position.
regards,
regards,
Most players would think the opposite-if you're hopelessly lost, it's best to resign and spend your energy on a game where you actually have a chance.
Hello... chess.com,
I'm really comfuse About The Value of the Rating in Live Chess. Can u tell me the calculation about plus and minus rating after done the match. Resignation point also always change.