Chessboard maker

Draw a chess position from a FEN string. Click a square to place or remove a piece, set whose move it is, and get a clean board diagram to drop inline in your document.

FEN chess position syntax

A board is written as a single FEN string — Forsyth–Edwards Notation, the standard way to record a chess position. The editor saves just that FEN line. You may put the word chess on its own line first if you like; it is optional and ignored.

The starting position

A FEN has six space-separated fields: piece placement, side to move, castling rights, en passant target, halfmove clock and fullmove number. The full starting position is below.

You write

rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1

You get

Piece placement

The first field lists the eight ranks from rank 8 (top) down to rank 1, separated by /. In each rank a letter is a piece and a digit is that many empty squares. Uppercase letters are white pieces, lowercase are black: K king, Q queen, R rook, B bishop, N knight, P pawn. The example below shows a lone white king on e1 and a black king on e8.

You write

4k3/8/8/8/8/8/8/4K3 w - - 0 1

You get

A real position

The w or b after the placement is the side to move; it is shown under the board. The remaining fields (castling, en passant, clocks) are kept exactly as you write them so your FEN round-trips unchanged. Here is the position after 1.e4 c5 2.Nf3.

You write

rnbqkbnr/pp1ppppp/8/2p5/4P3/5N2/PPPP1PPP/RNBQKB1R b KQkq - 1 2

You get

Cheat sheet

Write this	You get
`rank/rank/…/rank`	Eight ranks, rank 8 first, separated by slashes
`K Q R B N P`	A white king, queen, rook, bishop, knight, pawn
`k q r b n p`	The same pieces in black (lowercase)
`1`–`8`	That many empty squares in a rank
`w` / `b`	White or Black to move (second field)
`KQkq - 0 1`	Castling, en passant, halfmove and fullmove fields (kept verbatim)