It's the rating system. It tries to find your range as quickly as possible; hence the large rating jumps. Feel free to check out previous forum posts:
https://www.chess.com/forum/search?keyword=Glicko+Rating+system
Why does my rating go up so much in Chess.com
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I have been using Chess.com for past 1 year but I never played any rapid game until recently.
Now I played only 3 games in rapid category and all 3 I won. But my rating shot up 361 points(1561).
It seems weird.How close is Chess.com rating with FIDE rating? Do I get similar result if I play FIDE rated games?