Diagram Creator
What is a FEN?
A FEN (short for Forsyth-Edwards Notation) "record" defines a particular game position, all in one line of text. FEN records contain 6 fields. The separator between fields is a space. The fields are:- Piece placement (from White's perspective). Each rank is described, starting with rank 8 and ending with rank 1; within each rank, the contents of each square are described from file a through file h. White pieces are designated using upper-case letters ("KQRBNP"), Black by lowercase ("kqrbnp"). Blank squares are noted using digits 1 through 8 (the number of blank squares), and "/" separate ranks.
- Active color. "w" means white moves next, "b" means black.
- Castling availability. If neither side can castle, this is "-". Otherwise, this has one or more letters: "K" (White can castle kingside), "Q" (White can castle queenside), "k" (Black can castle kingside), and/or "q" (Black can castle queenside).
- En passant target square in algebraic notation. If there's no en passant target square, this is "-". If a pawn has just made a 2-square move, this is the position "behind" the pawn.
- Halfmove clock: This is the number of halfmoves since the last pawn advance or capture. This is used to determine if a draw can be claimed under the fifty move rule.
- Fullmove number: The number of the full move. It starts at 1, and is incremented after Black's move.
Examples
A games starting position: rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1 Note: This could also be written as: rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNRAfter 1. e4: rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1