Carlsen is a high-profile chess figure who has caused some controversy in recent years.
Last year, he settled a long-running legal dispute after accusing a rival of cheating in a tournament.
On Friday, he withdrew from the short version of the game due to an argument over his dress. Carlsen was also the reigning champion in Blitz and Rapid chess.
He added that he would not appeal the decision, saying: “Honestly, I’m too old at this point to worry too much.”
He said he wore jeans to lunch and “didn’t even think” about switching them for other pants when he went to the tournament.
He turned up in a shirt, jacket, dark jeans and dress shoes and played a few rounds before being asked to change.
When his offer to switch to the next day was rejected, Carlsen said it “became a bit of a matter of principle for me”.
In a statement, FIDE confirmed the 34-year-old had been fined $200 (£159) and said its rules were applied “impartially”. They cited a case where another player was fined the same day before changing his shoes.
