101 ( +1 | -1 ) Also Depends uponif you happen to be a Rook. Black KR's prefer the Right Side of the King, for instance. But joking aside... You probably don't want to castle to where you've moved a lot of pawn, or your opponent has already got a space advantage there or launched an attack there with a lot of pieces on the board. Also casling into an opponents open lines, with major pieces on the board will probably be very dangerous to you. Yet in some positions of less pieces, closer to endgame like, the king may be needed on the side attacked to act as a valuable defender there. Like to the side where the opponent is waging a pawn "majority Attack".for instance. Some more genrealization: Casltling to the opposite side as your opponent may result in mutual wing attacks being launched. If playing for a calmer position, usually casling to the same side is often safer. It is all higherly variable and situation dependent. And many exceptions will certainly exist to all these generalizations. Good Chess to you.
25 ( +1 | -1 ) I forgot where I readThat most games with whites who castle( I think 70 %) castle kingside. The Black was a different percentage, but also higher than queenside. But then, that might be because that's what turns up more likely.
42 ( +1 | -1 ) I think......that's because it's easier, less pieces to be moved. The faster the King is removed to 'safety', less concern about the King being involved in the skirmish for the centre & both rook connected sooner. That's why a higher percentage for King-side castling. But to choose which side is better does depends on the board and what you plan to do, playing aggresive or playing defense oriented.
27 ( +1 | -1 ) depends on the positionof the game. It may seem obvious that kingside castling is more frequent because one has to move less pieces to make it possible, yet there are times that castling queenside fits the game better. Just be sure not to castle "into trouble."